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  1. #1
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    Default Heat Pump/ AC unit breakers

    I've been noticing a string of Heat Pumps that have oversized breakers installed in the main panels. The units specify a maximum breaker size and when checking the main panel for this i've found numerous (in the past 40 or so inspections) to be oversized. Today the unit called for a 20A max breaker and a 30A breaker was servicing the HP's wiring. Am I mistaken in my process or are the installers around here just being liberal to avoid callbacks for tripping breakers? Anyone have any other insights? Gracias.

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  2. #2
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    Default Re: Heat Pump/ AC unit breakers

    The size of the breaker in the panel does not matter as long as the breaker is large enough to handle the heat pump, the wire is the correct size for the breaker, and HP is fused properly at the unit.


  3. #3
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by James Duffin View Post
    The size of the breaker in the panel does not matter as long as the breaker is large enough to handle the heat pump, the wire is the correct size for the breaker, and HP is fused properly at the unit.
    Not fully correct or clear as stated.

    "The size of the breaker in the panel does not matter as long as ... " there is overcurrent protection at the outdoor unit (condenser unit/heat pump unit/etc.). I realize that is what you meant when you added "and HP is fused properly at the unit.", but your statement first implies that the size of the breaker in the panel does not matter, and to a person who is not familiar with this, they may not make the connect.

    The better way to state it would be to say that the size of the breaker in the panel needs to be the same size, or smaller, as is stated on the nameplate - unless there is a fused disconnect at the outdoor unit (many times the disconnect at the outdoor unit is simply that - a disconnect - and thus the size of the breaker in the panel IS the breaker which needs to no larger than the rating shown on the nameplate.

    Semantics, you say, and yes, it is, but the way we say things often times comes back to bite us in the butt if we are not careful.

    Jerry Peck, Construction / Litigation Consultant
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  4. #4
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    Default Re: Heat Pump/ AC unit breakers

    Common violation by HVAC installers, especially if the unit's MOCP calls the odd sizes such as 25,35, and such.They just put in the next larger size.

    Another thing. You will find that most will use NM-B/Romex in the flex conduit to the unit. That is a no no also.


  5. #5
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Derek Guridi View Post
    Common violation by HVAC installers, especially if the unit's MOCP calls the odd sizes such as 25,35, and such.They just put in the next larger size.
    Over the last 2 years I've trained most HVAC contractors that does not work here - I look at the nameplate and the overcurrent size, and if they have not yet learned to make sure it is correct they *will* come back out and change it.

    Another thing. You will find that most will use NM-B/Romex in the flex conduit to the unit. That is a no no also.
    Yes, that too, and that one is taking longer for them to catch onto ... I don't know why, but they resist learning that one. Of course, though, that means coming back out and replacing with proper wiring.

    Jerry Peck, Construction / Litigation Consultant
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jerry Peck View Post
    Over the last 2 years I've trained most HVAC contractors that does not work here - I look at the nameplate and the overcurrent size, and if they have not yet learned to make sure it is correct they *will* come back out and change it.



    Yes, that too, and that one is taking longer for them to catch onto ... I don't know why, but they resist learning that one. Of course, though, that means coming back out and replacing with proper wiring.
    I was lucky, my first inspector was a friend of mine and he taught me this stuff about HVAC. I was trained right the first time.


  7. #7
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    Default Re: Heat Pump/ AC unit breakers

    Jerry, what's the proper wiring to run in flex conduit and how best to check? It's been my experience that the wiring is completely concealed from the exterior penetration into the unit. If NM-B is not allowed are the HVAC contractors supposed to install a junction box at the transition from in-wall wiring to change from NM-B to the approved wiring and then run it through the conduit?


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    Cool Re: Heat Pump/ AC unit breakers

    The best way to wire condensers is with made up "whips" using liquid-tite conduit, fittings and separate conductors.

    The breakers in the panel protect the cable--not the appliance. If the rating plate on the condenser calls for OCP less than what the breaker is rated for then a fused disconnect with appropriate fuses should be used. Also, if the rating plate calls for a fused disconnect then it must be fused as that is how that unit was tested.

    Note that breakers must be rated for HACR.

    Keep the fire in the fireplace.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Luc V. L. View Post
    Jerry, what's the proper wiring to run in flex conduit and how best to check? It's been my experience that the wiring is completely concealed from the exterior penetration into the unit. If NM-B is not allowed are the HVAC contractors supposed to install a junction box at the transition from in-wall wiring to change from NM-B to the approved wiring and then run it through the conduit?
    You make it sound like there is no exterior disconnect. Is this true?

    Normally the NM would enter the back of the disconnect and then switch to UF or a conduit system with individual conductors.

    All answers based on unamended National Electrical codes.

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    Cool Re: Heat Pump/ AC unit breakers

    UF is not the appropriate choice because it is designed and intended to be buried directly. It will be exposed on both ends, which it is not intended or allowed to do. Remember, there is great likelihood for physical damage to the wiring from weed eaters, kids, critters, UV rays, ozone, rocks thrown by lawn mower, rain/ snow/ ice, etc.

    Keep the fire in the fireplace.

  11. #11
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    Default Re: Heat Pump/ AC unit breakers

    UF is listed for use outside and buried. It is already UV resistant. It should not be getting damaged by getting wet from rain and snow. Also it is typically tie-wrapped on the line sets to protect it and provide for the securing requirements.

    The seal-tight whips you propose to use are not listed for use as protection from physical damage and would be just as prone to damage by weedeaters and children.

    All answers based on unamended National Electrical codes.

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    Default Re: Heat Pump/ AC unit breakers

    Jim is correct on both accounts: NM cable from inside the wall, through the wall and into a junction box or disconnect enclosure, from there properly rated wiring to the condenser unit (typically, this would be THWN, etc., in liquid tight); and that liquid tight is not rated as being suitable for protection from physical damage.

    UF cable can be used outside and exposed or underground, however, wherever UF cable emerges from the ground it needs to be protected from physical damage to a minimum depth of 18" into the earth and to a height of 8' or to the first enclosure, whichever comes first. Schedule 80 PVC is suitable for this, Schedule 40 is not, rigid metal conduit is suitable, and intermediate metal conduit is suitable for protection from physical damage.

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    Default Re: Heat Pump/ AC unit breakers

    Jerry, I appreciate your clarifications but would ask one more: What is the reference (NEC?) for what constitutes an acceptable form of protection for the exposed cable? The main reason I'm asking is because probably 75% of all new installs use Sealtite or generic liquidtite 'whips' with THHN or THWN wire.

    You confirmed my point at least in part that UF is not approved hanging in the breeze from disconnects to condensers even if Ziptied to the lineset and that was my main point.

    So,since Sch. 80 rigid conduit is not practical for these connections, what is? How about the liquidtite/steel flex conduit?
    TIA,

    Keep the fire in the fireplace.

  14. #14
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Bob Harper View Post
    What is the reference (NEC?) for what constitutes an acceptable form of protection for the exposed cable? The main reason I'm asking is because probably 75% of all new installs use Sealtite or generic liquidtite 'whips' with THHN or THWN wire.
    THHN is not suitable for use outside, even in a raceway, unless it is also dual rated such as THHN/THWN/etc., with at least one of the ratings having the 'W' in it for 'wet location'.

    You confirmed my point at least in part that UF is not approved hanging in the breeze from disconnects to condensers even if Ziptied to the lineset and that was my main point.

    So,since Sch. 80 rigid conduit is not practical for these connections, what is? How about the liquidtite/steel flex conduit?
    Nope, not suitable.

    The NEC is vague and limited on the information it provides (for the most part) for areas which require protection from physical damage - on place where the NEC does provide specific information, though, is for conductors emerging from grade.

    That information can be taken and applied as the code applicable information to other areas which refer to the otherwise vague 'protection from physical damage' limited information in the code.

    Typically, conductors which are rated for direct burial would be, should be, 'tougher' than conductors which are intended to be protected in raceways or an outer sheath. Thus, the requirements for protecting those 'tougher' conductors would surely be applicable to conductors which are not as 'tough' - reasonable presumption? It works for me when I explain it to electrical contractors as no person in their right mind would think that direct burial conductor are not as tough as conductors intended to be protected in a raceway or outer sheath.

    Then, the section goes on to address raceway damage, and raceways should certainly be 'tougher' than cables or conductors, another reasonable presumption, right?

    So, here goes:
    - 2008 NEC
    - - 300.5 Underground Installations.
    - - - (D) Protection from Damage. Direct-buried conductors and cables shall be protected from damage in accordance with 300.5(D)(1) through (D)(4).
    - - - - (1) Emerging from Grade. Direct-buried conductors and cables emerging from grade and specified in columns 1 and 4 of Table 300.5 shall be protected by enclosures or raceways extending from the minimum cover distance below grade required by 300.5(A) to a point at least 2.5 m (8 ft) above finished grade. In no case shall the protection be required to exceed 450 mm (18 in.) below finished grade.
    - - - - (2) Conductors Entering Buildings. Conductors entering a building shall be protected to the point of entrance.
    - - - - (3) Service Conductors. Underground service conductors that are not encased in concrete and that are buried 450 mm (18 in.) or more below grade shall have their location identified by a warning ribbon that is placed in the trench at least 300 mm (12 in.) above the underground installation.
    - - - - (4) Enclosure or Raceway Damage. Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in rigid metal conduit, intermediate metal conduit, Schedule 80 PVC conduit, or equivalent.

    The key, then, is this: "is subject to physical damage"

    IF the conductors/cable/raceway "is subject to physical damage", then the conductors or cable shall be in a raceway, and the raceway shall be "rigid metal conduit, intermediate metal conduit, Schedule 80 PVC conduit".

    Also, when one looks up PVC in the UL White Book, the UL White Book states that Schedule 80 is suitable for protection from physical damage and that Schedule 40 is not to be used where protection from physical damage is needed.

    So,since Sch. 80 rigid conduit is not practical for these connections, what is? How about the liquidtite/steel flex conduit?
    If the conductors are not subject to physical damage, then a lesser raceway may be suitable, and non-metallic liquidtight is suitable if the equipment vibrates if the liquidtight is not subject to physical damage, and any condenser unit which vibrates that much is in need of being checked out.

    With the conductors (typically THHN/THWN in non-metallic liquidtight) not being subject to physical damage for the most part, not in most installation I see, then the non-metallic liquidtight is okay.

    Last edited by Jerry Peck; 04-12-2012 at 04:30 PM. Reason: added last sentence
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    Default Re: Heat Pump/ AC unit breakers

    I operate from memory because the drudgery of bouncing thgrough the NEC is painful, but my recollection is that a motor load circuit can be sized up to five times the size of the running current. Somewhere in that circuit, ( dual element fuses, motor rated C/B or thermal overloads in the motor ), there must be something to insure it will shut down before it burns up. When started; a motor is a virtual electrical short trying to make something static rotate at say 1,600 RPMs instantly and within a second or two it changes from that tremendous short / current draw to it's normal running load. The load is to large to accomodate w/ normal numbers/sizes, but it changes in time so fast that most overload devices do not react quickly enough to trip or blow. So we just use larger than normal sizes for motors and they manage to hang in there by virtue of being too slow to trip.


  16. #16
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Garry Blankenship View Post
    I operate from memory because the drudgery of bouncing thgrough the NEC is painful, but my recollection is that a motor load circuit can be sized up to five times the size of the running current. Somewhere in that circuit, ( dual element fuses, motor rated C/B or thermal overloads in the motor ), there must be something to insure it will shut down before it burns up. When started; a motor is a virtual electrical short trying to make something static rotate at say 1,600 RPMs instantly and within a second or two it changes from that tremendous short / current draw to it's normal running load. The load is to large to accomodate w/ normal numbers/sizes, but it changes in time so fast that most overload devices do not react quickly enough to trip or blow. So we just use larger than normal sizes for motors and they manage to hang in there by virtue of being too slow to trip.
    The starting current for one of these motors is up to 6X the running current. The OCPD has to be designed to allow the motor to start without opening. Time delay fuses or inverse-time circuit breaker are typically set at up to 175% of the running current. An instantaneous trip CB at 700% the running current.

    The OCPD at the beginning of the circuit is there for short circuit and ground fault protection and is not there to protect the conductors from overload. That is left to the thermal protective device which may be integral or external of the unit.

    For A/C units, (conductor sizing and OCPD sizing) all of the information required should be on the nameplate of the unit. You can use the MCA for sizing the conductor and the Max OCPD for sizing the ground fault and short circuit protection. The OCPD value does not have to match the conductor size. For example a unit (under the 2008 or with MC cable) with an MCA of 24 amps and an OCPD value of 40 amps can have #12 conductors on a 40 amp inverse time circuit breaker.


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    Default Re: Heat Pump/ AC unit breakers

    I see over amp breakers when a system is replaced. The newer systems generally call for a MAX breaker size significantly less than the original system. I don't think the installers think about checking that.

    I see some of the installers on even new homes using SE cable for power to the compressor unit. When it's in weed eater territory, I report it and recommend adding conduit protection.

    The above statements are expressed solely as my opinion and in all probability will conflict with someone else's.
    Stu, Fredericksburg VA www.VaInspectionService.com

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    Wink Re: Heat Pump/ AC unit breakers

    I am a new member here and love learning more each day but a simple question gets turned into a 3 day event time after time. Lets keep answers simple and help each other. I don't think anyone cares which direction the wind is from in your state.....just my 2cents.


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jerry Peck View Post
    Jim is correct on both accounts: NM cable from inside the wall, through the wall and into a junction box or disconnect enclosure, from there properly rated wiring to the condenser unit (typically, this would be THWN, etc., in liquid tight); and that liquid tight is not rated as being suitable for protection from physical damage.

    UF cable can be used outside and exposed or underground, however, wherever UF cable emerges from the ground it needs to be protected from physical damage to a minimum depth of 18" into the earth and to a height of 8' or to the first enclosure, whichever comes first. Schedule 80 PVC is suitable for this, Schedule 40 is not, rigid metal conduit is suitable, and intermediate metal conduit is suitable for protection from physical damage.
    However, if the UF is not emerging from below grade the only guidance would be the loosely defined "subject to physical damage" which would leave this up to th inspection agency as to whether they would accept UF or require a means of protection.

    I have never seen the A/C wiring emerging from grade as the disconnect height normally leaves enough room to keep the wiring above the weedeater level.

    All answers based on unamended National Electrical codes.

  20. #20
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    Default Re: Heat Pump/ AC unit breakers

    Whatever happened to the 10% over fuse allowance for a/c's? Motors etc.. or did I read something wrong years ago.. or did they stop allowing? Or am I crazy... like everybody else?


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    Default Re: Heat Pump/ AC unit breakers

    Kenny, I am not sure what you are talking about with the 10% stuff, but the info needed is all on the data plate. This covers the minimum circuit ampacity and the maximum overcurrent protection size.

    All answers based on unamended National Electrical codes.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jim Port View Post
    However, if the UF is not emerging from below grade the only guidance would be the loosely defined "subject to physical damage" which would leave this up to th inspection agency as to whether they would accept UF or require a means of protection.
    Correct, which is why I specified (I added the underlining): "UF cable can be used outside and exposed or underground, however, wherever UF cable emerges from the ground it needs to be protected from physical damage ... "

    I have never seen the A/C wiring emerging from grade as the disconnect height normally leaves enough room to keep the wiring above the weedeater level.
    I see it quite frequently. They will position the condenser units away from the house/townhouse to reduce the noise at the house/townhouse, run from the junction box on/in the wall down underground and out to the condenser unit, where they emerge from grade to the condenser unit. The conductors going down into the grade are also 'emerging from grade' up to the junction box (just to clarify that 'emerging from grade' does not just apply to the outboard end).

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    Default Re: Heat Pump/ AC unit breakers

    The connection from the shut off to the condensor panel is subject to vibration, that's why UF is not sufficient or appropriate - UF is stiff and not suitable for repeated flexing or vibration resistance. It is also prone to weighted loads from snow, flexing in the wind, etc. UF connections to multiple-motor based exterior unit will not suffice. The jumper/whip, etc.from the disconnect to the exterior condensor requires a flexible connection. for example a Liquidtight flexible Metallic (insulated grounding conductor required). If necessary to protect from damage it can be guarded, etc. strapping to the refrigerant tubing is not properly supporting UF or any other cable and affords NO protection from damage.


  24. #24
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    The connection from the shut off to the condensor panel is subject to vibration, that's why UF is not sufficient or appropriate - UF is stiff and not suitable for repeated flexing or vibration resistance. It is also prone to weighted loads from snow, flexing in the wind, etc. UF connections to multiple-motor based exterior unit will not suffice. The jumper/whip, etc.from the disconnect to the exterior condensor requires a flexible connection. for example a Liquidtight flexible Metallic (insulated grounding conductor required). If necessary to protect from damage it can be guarded, etc. strapping to the refrigerant tubing is not properly supporting UF or any other cable and affords NO protection from damage.
    Why does it have to be insulated?


  25. #25
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Luc V. L. View Post
    I've been noticing a string of Heat Pumps that have oversized breakers installed in the main panels. The units specify a maximum breaker size and when checking the main panel for this i've found numerous (in the past 40 or so inspections) to be oversized. Today the unit called for a 20A max breaker and a 30A breaker was servicing the HP's wiring. Am I mistaken in my process or are the installers around here just being liberal to avoid callbacks for tripping breakers? Anyone have any other insights? Gracias.
    What I have observed - back at the main panel you will find the breaker that was probably correct for the original build. The newer replacement outside units don't require the ampacity of the originals (in some cases, even if the tonnage was increased). Addidtionally, the newer units will be labeled with more exacting breaker requirements. So, if the wire between the main panel and the outside unit's disconnect is appropiate, and the disconnect breaker has the characteristics sited on the unit's label - good to go.


  26. #26
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Robert Meier View Post
    Why does it have to be insulated?
    Good question. You are a sparky aren't you Robert ? H.W.s post stiputates flexible metallic conduit and I'm assuming that means steel. I have seen aluminum flex, but not aluminum based seal tight. I considered dissimilar metals, but I think steel and copper play well together. There is, I suppose, a romote possibility of a bare aluminum ground wyr which would not play well w/ steel - - - but that is quite a reach.


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    Default Re: Heat Pump/ AC unit breakers

    I think what might have been meant was that a EGC was required even in a metallic flex whip. This is a recent addition to the NEC. Prior to the change the metallic flex could be used as the EGC.

    All answers based on unamended National Electrical codes.

  28. #28
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Garry Blankenship View Post
    Good question. You are a sparky aren't you Robert ? H.W.s post stiputates flexible metallic conduit and I'm assuming that means steel. I have seen aluminum flex, but not aluminum based seal tight. I considered dissimilar metals, but I think steel and copper play well together. There is, I suppose, a romote possibility of a bare aluminum ground wyr which would not play well w/ steel - - - but that is quite a reach.
    Yes, the dissimilar metals thing is somewhat misunderstand. Just because two metals are different does not automatically mean that they cannot be used together. As you've mentioned copper and steel are used together all of the time without issue. We bond copper EGC's directly to steel boxes as one example. Even bare aluminum can be used in a steel raceway.


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Robert Meier View Post
    Even bare aluminum can be used in a steel raceway.
    Was unsure about that & probably wrong. I think Jim figured it out. I'm thinikn the word in H.W.s post was meant to be isolated, ( as in separate , not really isolated ), and not insulated to support the relatively recent code change disallowing the "metallic" part to be used as a ground conductor.

    It's not commonly stocked, but you can get PVC coated M/C cable. It is a cost saving miracle in wet and especially salt water environs.


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    The jumper/whip, etc.from the disconnect to the exterior condensor requires a flexible connection. for example a Liquidtight flexible Metallic (insulated grounding conductor required).
    First, I seldom see liquidtight metallic conduit, almost everyone here uses nonmetallic liquidtight conduit - but let's go with the metallic liquidtight ... why does the condenser unit require a flexible connection?

    Quote Originally Posted by Robert Meier View Post
    Why does it have to be insulated?
    Nothing in the code says the equipment grounding conductor needs to be insulated, and, if not required for flexibility, an equipment grounding conductor is not even required (provided the conditions are met for using using the metal conduit for the equipment ground).

    Quote Originally Posted by Jim Port View Post
    I think what might have been meant was that a EGC was required even in a metallic flex whip. This is a recent addition to the NEC. Prior to the change the metallic flex could be used as the EGC.
    If flexibility is not required "after installation", then the equipment grounding conductor is not required (with the conditions referenced above).

    - 350.60 Grounding and Bonding.
    - - Where used to connect equipment where flexibility is required after installation, an equipment grounding conductor shall be installed.
    - - Where flexibility is not required after installation, LFMC shall be permitted to be used as an equipment grounding conductor when installed in accordance with 250.118(6).
    - - Where required or installed, equipment grounding conductors shall be installed in accordance with 250.134(B).
    - - Where required or installed, equipment bonding jumpers shall be installed in accordance with 250.102.
    - - - FPN: See 501.30(B), 502.30(B), 503.30(B), 505.25(B), and 506.25(B) for types of equipment grounding conductors.

    - 250.118 Types of Equipment Grounding Conductors.
    - - (6) Listed liquidtight flexible metal conduit meeting all the following conditions:
    - - - a. The conduit is terminated in listed fittings.
    - - - b. For metric designators 12 through 16 (trade sizes through ½), the circuit conductors contained in the conduit are protected by overcurrent devices rated at 20 amperes or less.
    - - - c. For metric designators 21 through 35 (trade sizes ¾ through 1¼), the circuit conductors contained in the conduit are protected by overcurrent devices rated not more than 60 amperes and there is no flexible metal conduit, flexible metallic tubing, or liquidtight flexible metal conduit in trade sizes metric designators 12 through 16 (trade sizes through ½) in the grounding path.
    - - - d. The combined length of flexible metal conduit and flexible metallic tubing and liquidtight flexible metal conduit in the same ground return path does not exceed 1.8 m (6 ft).
    - - - e. Where used to connect equipment where flexibility is necessary after installation, an equipment grounding conductor shall be installed.

    - 250.134 Equipment Fastened in Place or Connected by Permanent Wiring Methods (Fixed) — Grounding.
    - - (B) With Circuit Conductors. By connecting to an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors.
    - - - Exception No. 1: As provided in 250.130(C), the equipment grounding conductor shall be permitted to be run separately from the circuit conductors.
    - - - Exception No. 2: For dc circuits, the equipment grounding conductor shall be permitted to be run separately from the circuit conductors.
    - - - - FPN No. 1: See 250.102 and 250.168 for equipment bonding jumper requirements.
    - - - - FPN No. 2: See 400.7 for use of cords for fixed equipment.

    Unless I am missing something, I don't see a requirement for the equipment grounding conductor to be insulated for that use.

    Nor can I find a requirement which specifies that the condenser unit is required to be installed and connected for flexibility after installation - but I may have missed that too.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jerry Peck View Post
    Unless I am missing something, I don't see a requirement for the equipment grounding conductor to be insulated for that use.

    Nor can I find a requirement which specifies that the condenser unit is required to be installed and connected for flexibility after installation - but I may have missed that too.
    I agree. IMO the flexible raceway is used simply because it's easier to install. You could connect the unit with a piece of conduit if you wanted. After all the copper connections to the unit are not flexible.

    So since flexibility is not required after installation then the LFMC could be used for the EGC if it meets the requirement for size and the OCPD limits in 250.118(6).


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    Default Re: Heat Pump/ AC unit breakers

    Suffice it to say, see both the .30 (Securing and Supporting) and .10 & .12 sections of the appropriate articles.

    When a prescriptive use or exception of a wiring method (for example its extra-building use, exposed, and most especially the method of securing & supporting, or lack thereof) may be employed in the manner installed only due to required flexibility following installation...it is disingenuous to claim that the conductors nor the raceway so installed, do not require flexibility upon/after their installation.

    If flexibility is required to minimize the transmission of vibration from equipment or to provide flexibility for equipment that requires movement after installation, an equipment grounding conductor of the wire type must be installed with the circuit conductors in accordance with 250.102(E), and it must be sized in accordance with 250.122, based on the rating of the circuit overcurrent device.


    The branch circuit ECG is not only serving as an ECG. It is serving as a bonding jumper. It is bonding not only the AC condensor unit, but the refrigerant (gas/liquid) metallic (copper) piping (tubing) system(s) which are both conductive, and present inside (should be bonded via the furnace or AirHandling Cabinet circuit) and extra-structure (outside the building). {such as 250.104, .104(B)}.

    ...


    A few more odd (?) things that have been thrown out in this discussion, responsive thereto:

    ECGs and Bonding Jumpers may not be aluminum when same runs or terminates outdoors within 18" of the ground/grade/earth. Few resideintial split AC condensors or HPs are placed such that the connection to the unit is greater than 18" from the ground/grade. Most every one placed outdoors and accessible from grade, remains accessible for contact by persons. It is rare indeed that such a unit is placed in a manner so as to assure that it is never wet, nor the approach to same is never wet.

    Pre-made (wired) whips of LFNC-B have to be listed as such. There use and lengths are furthermore limited.

    UF is not defacto sunlight resistant, it is only sunlight resistant when Listed and/or Listed and Labeled as such.

    The vast majority of the country experiences temperatures at or below 14 degrees F upon occasion. Regions which experience this regularly tend to avoid reliance on a weather tight and watertight wiring method which such protections deteriorate and become brittle because they have been exposed to such temperatures.

    I've seen statements, particularly by one individual, lately, frequently claiming that conductors for wiring are "dual" and/or slant rated & marked in a manner involving multiple marking designations with a slant. This is untrue. The tables for marking are both available in the NEC and in the UL Marking Guide pertaining to same. Such conductors for general wiring are not "slant" marked with multiple wiring type designations, nor are they "dual rated". A singular marking designation indicates the properties and temperatures of such conductors and that singular marking designation indicates what those temperature ratings are, and when those temperature ratings vary by location, dry; location, damp; or location, wet, it is again, indicated by the singular marking designation. They are not slant rated or multiply or dually marked.

    It has been stated on several recent discussions by certain individuals that the 2008 NEC only clarifies wet locations as within any underground raceway. This is untrue.

    2008 NEC 300.9 reads thusly:

    <B>300.9 Raceways in Wet Locations Above Grade. Where raceways are installed in wet locations abovegrade, the interior of these raceways shall be considered to be a wet location. Insulated conductors and cables installed in raceways in wet locations above grade shall comply with 310.8(C).

    2008 NEC 310.8 (C) and (D) read thusly:

    <B>310.8 Locations

    (C) Wet Locations. Insulated conductors and cables used in wet locations shall comply with one of the following:
    (1) Be moisture-impervious metal-sheathed.

    (2) Be types MTW, RHW, RHW-2, TW, THW, THW-2, THHW, THWN, THWN-2, XHHW, XHHW-2, ZW.

    (3) Be of a type listed for use in wet locations.

    (D) Locations Exposed to Direct Sunlight. Insulated conductors or cables used where exposed to irect rays of the sun shall comply with (D)(1) or (D)(2).
    (1) Conductors and cables shall be listed, or listed and marked, as being sunlight resistant.

    (2) Conductors and cables shall be covered with insulating material, such as tape or sleeving, that is listed, or listed and marked, as being sunlight resistant.
    Watertight and Weather tight are not the same thing. Watertight is not the ONLY consideration for such installations in the vast majority of the country.

    Pointing to 2008 NEC Article 100, Definitions:

    Watertight. Constructed so that moisture will not enter the enclosure under specified test conditions.


    Weatherproof. Constructed or protected so that exposure to the weather will not interfere with successful operation.
    FPN: Rainproof, raintight, or watertight equipment can fulfill the requirements for weatherproof wherevaring weather conditions other than wetness, such as snow, ice, dust, or temperature extremes, are not a factor.

    </B></B>It has been claimed that UF cable or other wiring method can be strapped upon the refrigerant tubing and relied upon same for both securement & supporting as well as protection from damage, while otherwise unguarded, unsupported, and unprotected from damage, out-doors (exterior to the building or structure), and this too is untrue. There is nothiing in either the UF nor the NM cable sections (when UF is used as permitted as NM) that permits this. The wiring method to the split AC or HP condensor outdoors is installed through and behind a panel (access/maintenance/servicing) on the device itself which allows access.

    2008 NEC 300.4 reads thusly:

    300.4 Protection Against Physical Damage
    (C) Cables Through Spaces Behind Panels Designed to Allow Access. Cables or raceway-type wiring methods, installed behind panels designed to allow access, shall be supported according to their applicable articles.

    Furthermore, the wiring method used for the outdoor branch circuit must be protected against deterioration:

    300.6 Protection Against Corrosion and Deterioration. Raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, fittings, supports, and support hardware shall be of materials suitable for the environment in which they are to be installed.

    Raceways outdoors are exposed to different temperatures (uncontolled environments, weather is ever changing), and often expand and contract. An example of this may be from the extreme of winter coldest night and the opposite extreme of the hottest day in the summer, with sun shining, reflective heat from surfaces, and heat of the conductors in use.


    300.7 Raceways Exposed to Different Temperatures.
    (A) Sealing. Where portions of a cable raceway or sleeve are known to be subjected to different temperatures and where condensation is known to be a problem, as in cold storage areas of buildings or when passing from the interior to the exterior of a building, the raceway or sleeve shall be filled with an approved material to prevent the circulation of warm air to a colder section of the raceway or sleeve. An explosiion proof seal shall not be required for this purpose.



    (B) Expansion Fittings. Raceways shall be provided with expansion fittings where necessary to compensate for thermal expansion and contraction.


    FPN: Table 352.44 and Table 355.44 provide the expansiion information for polyvinyl chloride (PVC) and for reinforced thermosetting resin conduit (RTRC), respectively.


    A nominal number for steel conduit can be determined by multiplying the expansiion length in Table 352.44 by 0.20. The coefficient of expansion for steel electrical metallic tubing, intermediate metal conduit, and rigid conduit is 1.170 x 10(4) (0.0000117 mm per mm of conduit for each deg. C in temperature change) {0.650 x 10 (4) (0.0000065 in. per inch of conduit for each deg. F in temperature change)}.


    A nominal number for aluminum conduit and aluminum electrical metallic tubing can be determined by mltiplying the expansion length in Table 352.44 by 0.40. The coefficient of expansion for aluminum electrical metallic tubing and aluminum rigid metal consuit is 2.34 x 10 (-5) (0.0000234 mm per mm of conduit for each deg. C in temperature change) {1.30 x 10(5) 0.000013 in. per inch of conduit for each deg. F in temperature change}.


    Few such split AC or HP units located at or just above grade (within 5-1/2 feet) are placed upon or supported by foundation systems and stablezied so as to not be subject to movement or heaving. Rarely are such units bolted or secured. More rare is the use of a spring balancing, anti-vibration bushings when such units are not mounted upon the actual building.

    The fact is the motor, fan, units are subject to movement, and despite having been installed perfectly plumb and level, this status changes, frequently, in the real world. They are subject to vibration even when installed perfectly plumb and level, it is their very nature. In otherthan high-wind & HURRICANE locations, they usually are simply set upon a premanufactured concrete or plastic skid pad, (if even), upon grade (finished or not) neither of which is secured, bolted, or attached to the ground, or each other, simply held in place by gravity in the vast majority of such installations throughout the country.

    The free-standing split condensing untis require a flexible connection not only due to vibration and assurances of safety electrically system-wise, but lightning, and and other effects. They are subject to interchange, (removal, replacement) just as for example a water heater is, and is likewise why same are, for example, not allowed to be welded in, but removable via unions or similar connections.

    Last edited by H.G. Watson, Sr.; 04-15-2012 at 02:00 PM.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    The connection from the shut off to the condensor panel is subject to vibration, that's why UF is not sufficient or appropriate - UF is stiff and not suitable for repeated flexing or vibration resistance. It is also prone to weighted loads from snow, flexing in the wind, etc. UF connections to multiple-motor based exterior unit will not suffice. The jumper/whip, etc.from the disconnect to the exterior condensor requires a flexible connection. for example a Liquidtight flexible Metallic (insulated grounding conductor required). If necessary to protect from damage it can be guarded, etc. strapping to the refrigerant tubing is not properly supporting UF or any other cable and affords NO protection from damage.
    Quote Originally Posted by H.G. Watson, Sr. View Post
    If flexibility is required to minimize the transmission of vibration from equipment or to provide flexibility for equipment that requires movement after installation, an equipment grounding conductor of the wire type must be installed with the circuit conductors in accordance with 250.102(E), and it must be sized in accordance with 250.122, based on the rating of the circuit overcurrent device.
    .
    The free-standing split condensing untis require a flexible connection not only due to vibration and assurances of safety electrically system-wise, but lightning, and and other effects. They are subject to interchange, (removal, replacement) just as for example a water heater is, and is likewise why same are, for example, not allowed to be welded in, but removable via unions or similar connections.
    I don't know about anyone else, but *I* have never seen a condenser unit walking around and shaking enough to require flexibility of the connection.

    1) The refrigerant lines are SOLID COPPER and are not flexible either.
    2) Liquidtight conduit with SOLID CONDUCTORS in it (yes, SOLID conductors are allowed) is no more flexible than UF cable.
    3) Snow loading on flexible liquidtight will pull it out of its fittings and/or break the fittings.

    Show us a REQUIREMENT which states that the condenser units REQUIRE liquidtight, in which case it would also REQUIRE stranded conductors.

    I'll be waiting for that. Thank you.

    If a free standing condenser unit is walking around and shaking enough to fall under that "If flexibility is required to minimize the transmission of vibration from equipment or to provide flexibility for equipment that requires movement after installation, an equipment grounding conductor of the wire type must be installed with the circuit conductors in accordance with 250.102(E), and it must be sized in accordance with 250.122, based on the rating of the circuit overcurrent device.", then forget about the liquidtight and stranded conductors and *write the unit up for repair or replacement*.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jerry Peck View Post
    I don't know about anyone else, but *I* have never seen a condenser unit walking around and shaking enough to require flexibility of the connection.

    1) The refrigerant lines are SOLID COPPER and are not flexible either.
    2) Liquidtight conduit with SOLID CONDUCTORS in it (yes, SOLID conductors are allowed) is no more flexible than UF cable.
    3) Snow loading on flexible liquidtight will pull it out of its fittings and/or break the fittings.

    Show us a REQUIREMENT which states that the condenser units REQUIRE liquidtight, in which case it would also REQUIRE stranded conductors.

    I'll be waiting for that. Thank you.


    If a free standing condenser unit is walking around and shaking enough to fall under that "If flexibility is required to minimize the transmission of vibration from equipment or to provide flexibility for equipment that requires movement after installation, an equipment grounding conductor of the wire type must be installed with the circuit conductors in accordance with 250.102(E), and it must be sized in accordance with 250.122, based on the rating of the circuit overcurrent device.", then forget about the liquidtight and stranded conductors and *write the unit up for repair or replacement*.
    You're a joke and a half Peck.

    The units require flexibility in the branch circuit wiring method so as to allow for maintenance, and replacement.

    Just as a water heater requires a connection to the plumbing that allows for removal and replacement without destroying componants of the water distribution system(s) (hot & cold).

    They (split AC & HP condensors) also require a flexibility due to vibration, and for temperature changes causing expansion and contraction in the wiring method. Removal without deconstructing the branch circuit wiring method is actually required.

    When a flexible conduit is employed - the reason for its selection, require it remain flexible following installation.

    The copper tubing used for refrigerant allows for some movement. It is not hard drawn copper.

    UF (or UF as NM) is not an appropriate wiring method in and of itself and by itself, for Bob's question or location.

    .


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    You're a joke and a half Peck.
    Possibly, but I'm not even half the joke you are.

    The units require flexibility in the branch circuit wiring method so as to allow for maintenance, and replacement.
    Nope, do not need it for EITHER.

    Just as a water heater requires a connection to the plumbing that allows for removal and replacement without destroying componants of the water distribution system(s) (hot & cold).
    Let's see ...
    - 1) You turn the breaker or disconnect off.
    - 2) You unscrew the cover over the junction box in the top of the water heater.
    - 3) You then turn off the cold water supply valve.
    - 4) You now cut the copper/PEX/etc. piping.
    - 5) You then remove the old water heater and install the new water heater.
    - 6) You then reconnect all the plumbing piping.
    - 7) You now reconnect the electrical to the new water heater junction box cover, connect the wiring to the water heater's wiring, then screw down the access cover.
    - 8) Finally you turn the disconnect back on.
    - 9) ... ummm ... no need for flexible connection to water heater ...

    No need for flexible connection to condenser unit either.

    Oh ... Wait ... that must be why some plumbers installed those flexible connectors between the water heater plumbing fittings and the plumbing lines of the house ... Check! Got it!

    Yep, you are the jokester for sure.

    They (split AC & HP condensors) also require a flexibility due to vibration, and for temperature changes causing expansion and contraction in the wiring method. Removal without deconstructing the branch circuit wiring method is actually required.
    Not on any that I have seen replaced. Maybe the installers down here in Florida do it so often that they have got it down pat?

    Liquidtight would MAKE IT EASIER, yes, BUT NOT REQUIRED.

    And, as I stated ... IF IT IS VIBRATING ENOUGH TO NEED A FLEXIBLE CONNECTION ... THE CONDENSER UNIT NEEDS TO BE REPAIRED OR REPLACED.

    I must say, Watson, that with the REQUIRED tie-down clips to hold that condenser unit in place during a high wind event, that sucker ain't going no place. No flexible connection is required ... makes it EASIER -sure, but EASIER is not the same as "required".

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Jerry Peck View Post
    Possibly, but I'm not even half the joke you are.



    Nope, do not need it for EITHER.



    Let's see ...
    - 1) You turn the breaker or disconnect off.
    - 2) You unscrew the cover over the junction box in the top of the water heater.
    - 3) You then turn off the cold water supply valve.
    - 4) You now cut the copper/PEX/etc. piping.
    - 5) You then remove the old water heater and install the new water heater.
    - 6) You then reconnect all the plumbing piping.
    - 7) You now reconnect the electrical to the new water heater junction box cover, connect the wiring to the water heater's wiring, then screw down the access cover.
    - 8) Finally you turn the disconnect back on.
    - 9) ... ummm ... no need for flexible connection to water heater ...

    No need for flexible connection to condenser unit either.

    Oh ... Wait ... that must be why some plumbers installed those flexible connectors between the water heater plumbing fittings and the plumbing lines of the house ... Check! Got it!

    Yep, you are the jokester for sure.



    Not on any that I have seen replaced. Maybe the installers down here in Florida do it so often that they have got it down pat?

    Liquidtight would MAKE IT EASIER, yes, BUT NOT REQUIRED.

    And, as I stated ... IF IT IS VIBRATING ENOUGH TO NEED A FLEXIBLE CONNECTION ... THE CONDENSER UNIT NEEDS TO BE REPAIRED OR REPLACED.

    I must say, Watson, that with the REQUIRED tie-down clips to hold that condenser unit in place during a high wind event, that sucker ain't going no place. No flexible connection is required ... makes it EASIER -sure, but EASIER is not the same as "required".
    Now you're not only spouting nonsense and misrepresenting what others (myself included) have said, you're also making up code.

    Tie-down clips are not REQUIRED for just above grade (3") set-in-place installed split HPs or AC condensors. You only require them due to a local rule for your region. Not in the mechanical, electrical, sections or codes in the IRC, IMC, or NEC.

    IF the installation/installer determines the use of flexible conduit for the installation, due to flexibility for future replacement, maintenance, etc. or to protect from the transmission of vibration to the electrical installation or to the building (noise for example), as necessary or required for the installation, then when so installed, and limited supported, ran, etc. FOR THAT PURPOSE, then the installation must remain flexible. I did not say the CODE required the use of either LFMC or LFNC, just that when it was employed, and in a manner of supporting and securing for those purposes ALLOWED, that it was disingenuous to assert that the installation was not required to be flexible. Removing/deconstructing part of an installed branch circuit beyond the outlet is removing permanent construction. Having to require same to replace the unit - means the original installation is in violation.

    And yes, the code does say the split HP or AC unit like any other appliance covered by that section, must be able to be replaced without removing the branch circuit.


    That Branch circuit is permanent construction (wiring system). Branch Circuit wiring method (including its support, protection, etc.) is neither "piping" or "ducting". The split HP or AC outside condensor must be able to be replaced without removing the Branch Circuit (that which extends beyond the last overcurrent device (i.e. that OCPD containing disconnect that was the topic of the discussion). That AC condensor has to be able to be replaced without deconstructing or deinstalling the permanently installed Branch Circuit. The IRC tells us this is so.

    Quote Originally Posted by 2009 IRC
    Chapter 13 GENERAL MECHANICAL SYSTEM REQUIREMENTS
    Section 1305 APPLIANCE ACCESS


    M1305.1 Appliance access for inspection service, repair and replacement.

    Appliances shall be accessible for inspection, service, repair and replacement without removing permanent construction, other appliances, or any other piping or ducts not connected to the appliance being inspected, serviced, repaired or replaced.
    I'll "Peck" that for you, so you can understand:

    Appliances shall be accessible for
    inspection,
    service,
    repair and
    replacement
    without removing
    permanent construction,
    other appliances,
    or any other piping or ducts not connected to the appliance being inspected, serviced, repaired or replaced.
    Note there is NO COMMA after "ducts".

    Therefore the applicable requirement is:

    Appliances shall be accessible for replacement without removing permanent construction. That permanent construction includes the branch circuit from its origin (last OCPD) as installed to its outlet.

    Since the piping (refrigerant) is connected to the appliance - it may be removed, altered, or destroyed when removing for replacement (after properly, safely, and lawfully first removing the refrigerant & oil from the appliance and piping, of course).


    UF is not permitted to be used as proposed by Jim P. Jumping as he proposed is in no way permitted: looping in free air, and strapped to refrigeration lines, is not running along the building surface, and is not properly supported or protected from damage. Furthermore it stiffens and deteriorates due to exposure to commonly experienced temperature lows in the vast majority of these United States, and flexes due to higher temperatures experienced in most outdoor installations exposed to sunlight, etc. It is not suitable, nor is it designed to be re-flexed, moved, re-bent following its origiinal installation, especially after years of exposure.

    The electrical chapters of the 2009 IRC and 2008 NEC disagree with you regarding what may be used for protection. Protection from damage is not limited or narrowly focused to Sch. 80 anything.


    Strapping is only REQUIRED for storage type water tanks (and water heaters) in seismic regions D1&D2 in the unammended IPC and IRC and in Seismic regions C for Townhomes in the unammended IRC.

    The unammended IPC and IRC require a reversable connection to the threaded connection (pipe dope only on male threads). They also specify connections between dissimilar materials in the potable distribution system. Neither does the code provide for cutting or damaging the existing potable distribution system - cold or hot water lines solely for replacement of a Water heater. For example 2009 IRC or 2009 IPC 605.24

    You're desperately flinging nonsense and trying to bury same in B.S.


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Now you're not only spouting nonsense and misrepresenting what others (myself included) have said, you're also making up code.

    Tie-down clips are not REQUIRED for just above grade (3") set-in-place installed split HPs or AC condensors. You only require them due to a local rule for your region. Not in the mechanical, electrical, sections or codes in the IRC, IMC, or NEC.
    You obviously do not know or understand codes as much as you say (and think) you do.

    The ENTIRE state of Florida requires tie-downs for condenser units ... AS DOES THE IRC.

    To wit:
    - M1307.1 General. Installation of appliances shall conform to the conditions of their listing and label and the manufacturer’s installation instructions. The manufacturer’s operating and installation instructions shall remain attached to the appliance.
    - M1307.2 Anchorage of appliances. Appliances designed to be fixed in position shall be fastened or anchored in an approved manner. In Seismic Design Categories D1 and D2, water heaters shall be anchored or strapped to resist horizontal displacement caused by earthquake motion. Strapping shall be at points within the upper one-third and lower one-third of the appliance’s vertical dimensions. At the lower point, the strapping shall maintain a minimum distance of 4 inches (102 mm) above the controls.

    Not only are condenser units anchored to resist uplift and lateral loads from high winds, they are also anchored to resist seismic forces - and when an appliance is "designed to be fixed in position", like a condenser unit, the appliance "shall be fastened or anchored in an approved manner."

    Note only do condenser units come with mounting holes in their bases (look at the various installation instructions if you do not believe it - here are two from Trane
    - http://sbeelectricandhvac.com/doc_do...its-2ttb3.html
    - http://sbeelectricandhvac.com/doc_do...s-4ttb3-d.html

    And yes, the code does say the split HP or AC unit like any other appliance covered by that section, must be able to be replaced without removing the branch circuit.
    Huh? Who said anything about "removing" the branch circuit? Another figment of your imagination, Watson.

    Whether or not the connection method is liquidtight or otherwise, the branch circuit is not "removed", it is "disconnected" from the appliance.

    Appliances shall be accessible for
    inspection,
    service,
    repair and
    replacement
    without removing
    permanent construction,
    other appliances,
    or any other piping or ducts not connected to the appliance being inspected, serviced, repaired or replaced.
    Note there is NO COMMA after "ducts".

    Therefore the applicable requirement is:

    Appliances shall be accessible for replacement without removing permanent construction. That permanent construction includes the branch circuit from its origin (last OCPD) as installed to its outlet.
    Watson ... you been taking your meds lately?

    READ what I wrote - which was nothing about removing permanent construction. This is from above, I will REPEAT IT FOR YOU:

    "Huh? Who said anything about "removing" the branch circuit? Another figment of your imagination, Watson.

    Whether or not the connection method is liquidtight or otherwise, the branch circuit is not "removed", it is "disconnected" from the appliance."

    UF is not permitted to be used as proposed by Jim P.
    You have said that now, what, 2-3-4 times? I have asked now, what, 2-3-4 times for your supporting code reference ... oh, wait ... THIS IS ANOTHER OF THOSE TIMES when Watson says something and then refuses to back it up.

    Watson ... BACK UP WHAT YOU SAY with a code reference ...

    UF not allowed? BACK IT UP WITH CODE.

    Condenser units do not have to be anchored down? BACK IT UP WITH CODE.

    Condenser units require a flexible wiring method? BACK IT UP WITH CODE.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

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    Default Re: Heat Pump/ AC unit breakers

    I have seen hundreds of units that are almost a pile of rust that were wired with UF without significant damage that were secured to the line sets. Doesn't seem like the inspection agencies have that much of an issue with the use of UF.

    All answers based on unamended National Electrical codes.

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    Default Re: Heat Pump/ AC unit breakers

    Peck you're off your rocker.

    Quote Originally Posted by Jerry Peck

    The ENTIRE state of Florida requires tie-downs for condenser units ... AS DOES THE IRC.

    To wit:
    - M1307.1 General. Installation of appliances shall conform to the conditions of their listing and label and the manufacturer’s installation instructions. The manufacturer’s operating and installation instructions shall remain attached to the appliance.
    - M1307.2 Anchorage of appliances. Appliances designed to be fixed in position shall be fastened or anchored in an approved manner. In Seismic Design Categories D1 and D2, water heaters shall be anchored or strapped to resist horizontal displacement caused by earthquake motion. Strapping shall be at points within the upper one-third and lower one-third of the appliance’s vertical dimensions. At the lower point, the strapping shall maintain a minimum distance of 4 inches (102 mm) above the controls.
    That doesn't say what you claim it says. Interesting I cited 2009 IRC you've selectively cut and pasted from a different and un-referenced source or edition.

    Quote Originally Posted by Jerry Peck
    Not only are condenser units anchored to resist uplift and lateral loads from high winds, they are also anchored to resist seismic forces - and when an appliance is "designed to be fixed in position", like a condenser unit, the appliance "shall be fastened or anchored in an approved manner."
    The code doesn't state that. You're "Jerrying" again and masturbating the code. You're engaging in the usual burring in B.S. knowing full well that few, if any will actually read the rest, at best skim, and you do so as a means to cover the crap you fling like a dog kicking up the grass after he's left a pile on the sidewalk. I'm done with responding on this tread to you. Its up to you to prove a permissive or prescribed use of UF as Port claimed (in free air or strapped merely to the refrigerant lines out and away from building and to the condensor, not burried, or surrpoted in any other manner) in either the Article on UF, the article for NM (334) applicable when UF is used as NM, or Article 300. You won't, because you cant, because it isn't. Mixing in yet another metephore, Fork time, done 'nuff ya.


    If the conditions of the installation require flexibility (ex. proximiy of other appliances, perm. construction, etc. so as to remove and replace the appliance, or for example to avoid vibration transmission into the building)than the conditions of the installation that required flexiblity, continue to do so following installation.

    Robert, Garry, et. al.:

    If the grounding termination for the circuit (in this case the split AC or HP condensor), is within 18" of the ground (earth, dirt, grade) than the use of aluminum for a grounding conductor is not permitted.

    Last edited by H.G. Watson, Sr.; 04-17-2012 at 02:30 AM. Reason: Giving up arguing with berserk Peck.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Robert, Garry, et. al.:

    If the grounding termination for the circuit (in this case the split AC or HP condensor), is within 18" of the ground (earth, dirt, grade) than the use of aluminum for a grounding conductor is not permitted.
    You chastised Jerry for not providing the proper code sections so how about doing the same. What code section prohibits an aluminum EGC within 18" of the earth (for the record 250.64(A) is not applicable to this question). And what code section specifies that an AC unit requires a wiring method that is flexible?


  41. #41
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    Default Re: Heat Pump/ AC unit breakers

    PVC is rigid, although by applying heat it becomes flexible enough to be bent, but once the heat is removed it is again rigid. Article 352 is even titled Rigid Polyvinyl Chloride Conduit.
    Galvanized rigid conduit takes a bender and many pounds of pressure to be applied in order to be bent. EMT is rigid and also requires a bender and the application of many pounds of force although less than GRC or IMC due to the reduced wall thickness.

    Both NM and UF cable are flexible ie not rigid. The pressure needed to change the shape of either of these NM cables is nowhere near the amount needed to bend a conduit mentioned above. If they where not flexible the product could not be shipped in a roll and unrolled in order to install them.

    Here is the section about securing NM cables which also applies to Type UF cables. I do not see anywhere in this section nor Article 300 that states that the cables cannot be secured to the line sets. The one prohibition is that I cannot support or secure tha cables to other raceways or conduits unless it is listed as suitable as shown in the code cite below.

    (B) Raceways Used as Means of Support.
    Raceways
    shall be used only as a means of support for other raceways,
    cables, or nonelectrical equipment under any of the
    following conditions:
    (1) Where the raceway or means of support is identified for
    the purpose
    (2) Where the raceway contains power supply conductors
    for electrically controlled equipment and is used to support
    Class 2 circuit conductors or cables that are solely
    for the purpose of connection to the equipment control
    circuits
    (3) Where the raceway is used to support boxes or conduit
    bodies in accordance with 314.23 or to support luminaires
    in accordance with 410.36(E)

    (C) Cables Not Used as Means of Support.
    Cable wiring
    methods shall not be used as a means of support for other

    cables, raceways, or nonelectrical equipment.

    334.30 Securing and Supporting.
    Nonmetallic-sheathed
    cable shall be supported and secured by staples, cable ties,
    straps, hangers, or similar fittings designed and installed so
    as not to damage the cable, at intervals not exceeding 1.4 m
    (4
    12 ft) and within 300 mm (12 in.) of every outlet box,
    junction box, cabinet, or fitting. Flat cables shall not be
    stapled on edge.
    Sections of cable protected from physical damage by raceway

    shall not be required to be secured within the raceway

    Since most know the code is a permissive document if it is not prohibited, it is allowed by the code.


    All answers based on unamended National Electrical codes.

  42. #42
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    Default Re: Heat Pump/ AC unit breakers

    EGC, GEC, potato, tomatoe, whatever.

    All answers based on unamended National Electrical codes.

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    You're "Jerrying" again ...
    If I am "Jerrying" up the code again, then you are "Watsoning" (also known as "Waltzing" - otherwise known as "dancing") around without any code supporting hose of any type. By the way, you really look silly standing there with your hand in your pocket moving it back and forth like that, looks like you wet your pants too ...

    Watson,

    I will try to make this question r-e-a-l s-i-m-p-l-e for you:
    - What do you put through "mounting holes", what do you put that too, and what is the purpose of "mounting" something in place?
    - (hint) You put anchors through "mounting holes", and you put them through into something rigid, like the concrete or other approved pad or stand the instructions state, and when you out those anchors through the mounting holes into the pad or stand, you are rigidly securing the unit in place.

    Just like what this calls for:
    - M1307.2 Anchorage of appliances. Appliances designed to be fixed in position shall be fastened or anchored in an approved manner.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Todd Edly View Post
    I am a new member here and love learning more each day but a simple question gets turned into a 3 day event time after time. Lets keep answers simple and help each other. I don't think anyone cares which direction the wind is from in your state.....just my 2cents.
    Todd,
    You have fallen down the wrong rabbit hole for simple answers. There is to many experienced minds at work here. This tea party has a lot of chairs and a lot of opinions with varying reasoning. A simple answer is at times only expedient but not complete and informative.

    Despite the perceived voluminous verbiage and quipping between members, you will also be able to gleam additional information that can be applied to other situations.


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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    If the grounding termination for the circuit (in this case the split AC or HP condensor), is within 18" of the ground (earth, dirt, grade) than the use of aluminum for a grounding conductor is not permitted.
    So, how do you deal with underground aluminum? Or can we assume that underground splicing/terminations are OK but that once at the surface they need to be elevated 18"?

    Last edited by Bill Kriegh; 04-19-2012 at 05:40 AM.
    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

  46. #46
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    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by Robert Meier View Post
    You chastised Jerry for not providing the proper code sections so how about doing the same. What code section prohibits an aluminum EGC within 18" of the earth (for the record 250.64(A) is not applicable to this question). And what code section specifies that an AC unit requires a wiring method that is flexible?

    Prohibiting an aluminum EGC from terminating within 18" of the ground/dirt/grade outdoors ? Is that your question...because that's what I said regarding yours and GB's posts 26 & 28.

    2008 NEC, Chapter 2, Article 250, Part VI, Section 120, Subsection B.

    Last sentance {2008 NEC 250.120(B): "...Aluminum or copper-clad alumminum conductors shall not be terminated within 450 mm (18 in.) of the earth."

    (Note: Equipment Grounding Conductors are not limited to wire(s); Branch Circuit Conductors originate at the source containing OCPD and terminate at the outlet - in this case the utilization equipment, behind the split ac or hp condensor's integral access panel-cover plate or door.

    I don't know why you're referencing 250.64.


  47. #47
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    Cool anchoring units

    With regards to split systems, I have NEVER seen a condenser bolted down in a residential application anywhere from central SC to Pa. I have seen a few condensers located on or near the coast bolted down. I have never seen a furnace, air handler/ coil or boiler bolted down indoors in a residential application. Moreover, there are not bolt holes or tabs that are readily accessible that appear to be designed for installation anchoring. There are tabs or bolt holes used for shipping purposes. If you'll note the Trane manuals JP referenced, those plastic tabs get chopped off with a hammer and chisel to get the condenser off the pallette, which I've done a bunch of. I do not see anywhere in those manuals where it clearly instructs you to 'anchor' or otherwise secure the condenser as far as the mfrs. listed instructions go. Sure, local codes may add that as an ordinance but I don't see it in the manuals.

    As for the 'permanent construction' component, the way I read that is not referencing if the unit or its appendages are permanent or not but meaning not having to remove walls, floors, ceilings or other equipment to get to it that are NOT attached or integral to the appliance in question. Cutting linesets to condensers and coils, electrical cables and control wiring, gas and oil lines, water pipes and air ducts are all common practices expected with changing out appliances so there is no applicable code provision requiring all these 'permanent' components to have quick disconnect features that I see.

    I see enough exposed UF to condensers chewed up by weedeaters, critters, beetles, etc. to tell me no type of NM cable should be allowed to run exposed to condensers. The fact that liquidtite flexible polymeric conduit is not on the 'approved' list of protection for electrical cables is silly to me. It is the preferred method of connection and I have never seen one cut or otherwise penetrated except by vandals who chopped the lineset to steal an entire condenser and took an axe to the whip.

    Keep the fire in the fireplace.

  48. #48
    Robert Meier's Avatar
    Robert Meier Guest

    Default Re: Heat Pump/ AC unit breakers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Prohibiting an aluminum EGC from terminating within 18" of the ground/dirt/grade outdoors ? Is that your question...because that's what I said regarding yours and GB's posts 26 & 28.

    2008 NEC, Chapter 2, Article 250, Part VI, Section 120, Subsection B.
    Thanks, that's what i was looking for.


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