Thread: Question RE: FAU disconnect

Does a furnace located within an interior closet (not attic) have to have a means of disconnect, such as a switch?

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They do where I live. The furnace disconnect switch is for protection of the furnace repairman, no matter where it is located.

They do where I live as well. The cheapest way to comply in my area is to install a lock out type device in the panel. I'm not sure what they are actually called, but they are the brass colored ones in newer panels........the ones can fall out when you pull the deadfront.

Originally Posted by Marc M

Does a furnace located within an interior closet (not attic) have to have a means of disconnect, such as a switch?

I presume you are also referring to a furnace with air conditioning? Yes, there needs to be a disconnect at the equipment (within the closet in your example, if not in a closet then within 50 feet straight-line sight).

Originally Posted by Brandon Whitmore

The cheapest way to comply in my area is to install a lock out type device in the panel.

Not allowed to use a lockout *in place of* a disconnect at (and within 50 feet straight-line sight) of the air conditioning units.

Originally Posted by Brandon Whitmore
The cheapest way to comply in my area is to install a lock out type device in the panel.

Not allowed to use a lockout *in place of* a disconnect at (and within 50 feet straight-line sight) of the air conditioning units. __________________

Correct-- just furnaces.

Jerry, what are those brass colored lock outs actually called?

Originally Posted by Brandon Whitmore

Jerry, what are those brass colored lock outs actually called?

Brandon,

I haven't seen the brass ones, but if they are like the black ones I see ... they are called lockouts (at least that is what I've always heard them called and what I've always called them) as they enable the person working on the equipment to place a small lock in the hole and lock the breaker from being turned back on.

I suspect that 'lockout' is a slang term as the code simply says: "The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in place with or without the lock installed."

Originally Posted by Jerry Peck

I presume you are also referring to a furnace with air conditioning? Yes, there needs to be a disconnect at the equipment (within the closet in your example, if not in a closet then within 50 feet straight-line sight).



Not allowed to use a lockout *in place of* a disconnect at (and within 50 feet straight-line sight) of the air conditioning units.

I was referring to the FAU only. I know about the AC disco.
What about if the FAU was plugged into a receptacle via cord? Is that a means of disconnect?
I've never seen a switch in a hall closet, garage etc.... where a FAU was installed. Just plug-n-cord.

I have always considered the plug and cord as an approved means of disconnect. I don't recall ever having seen a switched FAU - not installed in a closet, anyway. By coincidence I came across my first ever FAU today which did not have a lock-out switch on the cabinet.

ip

Originally Posted by Ian Page

I have always considered the plug and cord as an approved means of disconnect. I don't recall ever having seen a switched FAU - not installed in a closet, anyway. By coincidence I came across my first ever FAU today which did not have a lock-out switch on the cabinet.

ip

IP,
Thanks, neither have I. Id like to see the NEC or IRC if someone could kindly assist.

Originally Posted by Marc M

I was referring to the FAU only. I know about the AC disco.
What about if the FAU was plugged into a receptacle via cord? Is that a means of disconnect?
I've never seen a switch in a hall closet, garage etc.... where a FAU was installed. Just plug-n-cord.

FAU is what, a gas fired furnace? Not sure there is an approved and listed cord and plug for that use.

I know that when it is an air handler unit with an evaporator coil and electric strips (either solely electric strips or back up for a heat pump) that there is no approved and listed cord and plug for that use - and, no, dryer and range cords are not suitable for that use.

*IF* that appliance is *listed for use with* as cord and a plug, *AND*, if there is a cord and plug *listed for use with* that appliance, then (and only then) would a cord and plug be acceptable to be used with that appliance, in which case the plug would be an approved disconnect for that appliance.

Do you have installation instructions for that appliance (that FAU) and does it list a cord and plug as an option to use for the electrical connection? If not, then a cord and plug is not allowed to be used.

No such chance for a installation spec sheet. So where in the NEC does it say that an FAU (forced air unit) has to be equipped with a disconnect at the unit?

My older copy of the UMC says this.

309.0 Electrical Connections
Equipment regulated by this code requiring electrical
connections of more than fifty (50) volts shall have a
positive means of disconnect adjacent to and in sight
from the equipment served.

Then is goes on to describe the service plug.
Can we assume that the unit plug in - in the heater compartment
fulfills this requirement?

CEC - Based on NEC
422-31. Disconnection of Permanently Connected Appliances
(a) Rated at Not Over 300 Volt-amperes or 1/8 Horsepower
for permanently connected appliances rated at not over 300 volt-amperes
or 1/8 hp, the branch-circuit over current device shall be permitted to serve
as the disconnection means.

mf

Originally Posted by John Kogel

They do where I live. The furnace disconnect switch is for protection of the furnace repairman, no matter where it is located.

Please cite your prevailing code for this remark.
Especially where the phrase disconnect switch is concerned.

I don't see this anywhere........

mf

Originally Posted by Marc M

So where in the NEC does it say that an FAU (forced air unit) has to be equipped with a disconnect at the unit?

FAU (forced air unit) *could be* an air handler for an air conditioning system - which is why I asked for clarification as to whether there was an evaporator coil there also.

The disconnect is required by this: (underlining and bold are mine)
- ARTICLE 422 Appliances
- - III. Disconnecting Means
- - - 422.30 General.
- - - - A means shall be provided to disconnect each appliance from all ungrounded conductors in accordance with the following sections of Part III. If an appliance is supplied by more than one source, the disconnecting means shall be grouped and identified.
- - - - 422.31 Disconnection of Permanently Connected Appliances.
- - - - - (A) Rated at Not over 300 Volt-Amperes or 1/8 Horsepower. For permanently connected appliances rated at not over 300 volt-amperes or 1/8 hp, the branch-circuit overcurrent device shall be permitted to serve as the disconnecting means.
- - - - - (B) Appliances Rated over 300 Volt-Amperes or 1/8 Horsepower. For permanently connected appliances rated over 300 volt-amperes or 1/8 hp, the branch-circuit switch or circuit breaker shall be permitted to serve as the disconnecting means where the switch or circuit breaker is within sight from the appliance or is capable of being locked in the open position. The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in place with or without the lock installed.
- ARTICLE 440 Air-Conditioning and Refrigerating Equipment
- - 440.14 Location.
- - - Disconnecting means shall be located within sight from and readily accessible from the air-conditioning or refrigerating equipment. The disconnecting means shall be permitted to be installed on or within the air-conditioning or refrigerating equipment.
- - - The disconnecting means shall not be located on panels that are designed to allow access to the air-conditioning or refrigeration equipment or to obscure the equipment nameplate(s).
- - - - Exception No. 1: Where the disconnecting means provided in accordance with 430.102(A) is capable of being locked in the open position, and the refrigerating or air-conditioning equipment is essential to an industrial process in a facility with written safety procedures, and where the conditions of maintenance and supervision ensure that only qualified persons service the equipment, a disconnecting means within sight from the equipment shall not be required. The provision for locking or adding a lock to the disconnecting means shall be installed on or at the switch or circuit breaker and shall remain in place with or without the lock installed.
- - - - Exception No. 2: Where an attachment plug and receptacle serve as the disconnecting means in accordance with 440.13, their location shall be accessible but shall not be required to be readily accessible.
- - 440.13 Cord-Connected Equipment.
- - - For cord-connected equipment such as room air conditioners, household refrigerators and freezers, drinking water coolers, and beverage dispensers, a separable connector or an attachment plug and receptacle shall be permitted to serve as the disconnecting means.

The above shows: a) a disconnect is required; b) that the disconnect may be the breaker with a lockout device; c) except if the equipment is air conditioning equipment, then the breaker is not allowed to be the disconnect, even with a lockout device.

Not sure if I covered all of your questions?

added with edit: added "1/8" in front of "horsepower" and "hp" as it did not copy as paste there for some reason

Here's a question I bet lots of guys reading this post are wondering right now.
But - they're not going to admit it.

So I'll ask for everybody.
Jerry might be able to enlighten us.

Exactly what would be a definition or explanation
of "300 volt-amperes"
And how does it compare/relate to the electrical system
and motor for a typical 65,000 BTU mid efficiency FAU, for example.

Thanks in advance.
mf

Originally Posted by matt faust

My older copy of the UMC says this.

309.0 Electrical Connections
Equipment regulated by this code requiring electrical
connections of more than fifty (50) volts shall have a
positive means of disconnect adjacent to and in sight
from the equipment served.

Then is goes on to describe the service plug.
Can we assume that the unit plug in - in the heater compartment
fulfills this requirement?

CEC - Based on NEC
422-31. Disconnection of Permanently Connected Appliances
(a) Rated at Not Over 300 Volt-amperes or 1/8 Horsepower
for permanently connected appliances rated at not over 300 volt-amperes
or 1/8 hp, the branch-circuit over current device shall be permitted to serve
as the disconnection means.

mf

Matt..you are the man. Thanks

300 volt-amperes is another way to say 300 watts
Heres a link to review
How to Convert Watts to VA and KVA to KW Simplified -- Converting Volt-amps to Watts the easy way

I just noticed that in the code section I posted above, that where it says "300 Volt-Amperes or Horsepower" the horsepower size did not copy and paste with the other content - I have no idea why the horsepower size did not copy and paste.

Wherever it says this: "300 Volt-Amperes or Horsepower" it should say this "300 Volt-Amperes or 1/8 Horsepower" (or 1/8 hp).

I've posted that section on other occasions and I never noticed that the 1/8 did not copy and paste.

So ... if the FAU has a motor rated at 1/8 hp or less *and* the total appliance rating is also less than 300 volt-amps (as Ken said, that would be equivalent to 300 watts) then (A) would apply, otherwise (B) applies.

Look at the rating on the FAU and see what it rating is. However, the only difference that would make would be whether or not the breaker would be allowed to serve as the disconnecting means as allowed in (A).

I am going back to edit the code section and insert the "1/8" where it should be.

Originally Posted by matt faust

Please cite your prevailing code for this remark.
Especially where the phrase disconnect switch is concerned.

I don't see this anywhere........

mf

I would have to do homework to find it, and whatever the precise wording may be, it would not apply to you in the Golden State anyway. That is why I started my statement with "where I live".

I don't have to justify everything I say with quotes from a code book. I know I'm lucky that way. We have licensing but not by realtor associations like some of you'all.

If a furnace switch is not present and the E panel (or a cord and plug, never see that) is not in the same room, I would call for a furnace switch to be installed. I don't see how it serves my client to find ways for a switch NOT to be installed, unless my client is the seller or a realtor. It's a basic safety item.

Originally Posted by matt faust

Exactly what would be a definition or explanation of "300 volt-amperes"

And how does it compare/relate to the electrical system
and motor for a typical 65,000 BTU mid efficiency FAU, for example.

Matt,

For a FAU which is gas or oil fired, and there is no computer controller in it, and nothing electrical in it other than the blower motor, the 300 volt-amperes would not come into play - the horsepower rating of the motor would be the controlling factor.

My guess is that the horsepower of the motor is going to be 1/2 hp power or more, and the controlling size for hp is 1/8 hp or less, or over 1/8 hp.

All that does, though, is if the motor is 1/8 hp or less, then the breaker would be allowed to serve as the disconnect. With a motor over 1/8 hp the other disconnect rules apply.

I doubt there is a FAU which would fall at 1/8 hp or less for the motor, and if one did, then the total rating of the appliance would also need to fall under 300 watts (300 volt-amperes) too in order to used the breaker as the disconnect and not have to follow the other disconnecting means requirements (within sight of, lock out, etc.).

Basically speaking, if it draws more than 2.5 amps at 120 volts then (B) and the disconnecting rules apply.

Disconnect required here. Easiest, best, reasonable cost and standard practice around here is to mount a 1900 box with an SSY on the side of the unit.
Jerry in reference to your last post about amperage, etc. Not that many years ago, Janitrol/Goodman and somebody else, might have been York or Rheem, can't remember, were shipping their furnaces out with 3A plug-in car fuses on the control board for protection. Guys were coming into the supply houses bitching about the fuses popping a lot. Nobody wants annoying service calls with pissed of customers. Guys (myself included) were just replacing the 3A with 5A fuses, no problems after that. Factory rep's gave the unofficial approval for the swap out. Under that scenario your 300 millA would clearly seem to apply.

Originally Posted by Markus Keller

Jerry in reference to your last post about amperage, etc. Not that many years ago, Janitrol/Goodman and somebody else, might have been York or Rheem, can't remember, were shipping their furnaces out with 3A plug-in car fuses on the control board for protection. Guys were coming into the supply houses bitching about the fuses popping a lot. Nobody wants annoying service calls with pissed of customers. Guys (myself included) were just replacing the 3A with 5A fuses, no problems after that. Factory rep's gave the unofficial approval for the swap out. Under that scenario your 300 millA would clearly seem to apply.

Markus,

Sounds to me like the manufacturer was trying to accommodate some contractors/architects/designers request for units which did not need the disconnect or the lock out devices and tried to make a unit which fell under that 300 volt-ampere rating (2.5 amp at 120 volts) and did not account for fan surge starting current or something else.

Shows you what manufacturers will try to do for a specific market niche.

Probably had a large order and the designer figured they could say $0.50 per system for not needing a lock out at the breaker, and that $0.50 times, say, 100,000 units would save the designers client $50,000 right at the get go - so they thought ... figure they had a 25% service call ratio for replacing those fuses and that would mean that trying to save that $50k actually may have cost them 25,000 service calls at $50 each (minimum) or about $1.25mil ... those things almost always seem to backfire that way.

Originally Posted by John Kogel

I would have to do homework to find it, and whatever the precise wording may be, it would not apply to you in the Golden State anyway. That is why I started my statement with "where I live".

I don't have to justify everything I say with quotes from a code book. I know I'm lucky that way. We have licensing but not by realtor associations like some of you'all.

If a furnace switch is not present and the E panel (or a cord and plug, never see that) is not in the same room, I would call for a furnace switch to be installed. I don't see how it serves my client to find ways for a switch NOT to be installed, unless my client is the seller or a realtor. It's a basic safety item.

Matt, some times you have to look beyond the codes and ask yourself what is the safe thing to do. the codes are there to enforce safety standards but going beyond them is sometimes what is best for those concerned. Maybe there is a code there out there, but going beyond for safety reasons within reason is in my books always a good thing to do. Always better safe than sorry!! the codes might be good but can you be better? that to me is the difference between a good inspector and a great one.

imo

Originally Posted by Bill Hetner

the codes might be good but can you be better?

Can you do better than the codes? I would hope so ... the codes are MINIMUM requirements, they are the WORST one is legally allowed to do .

Codes are not 'good', 'better', or 'best', the codes are simply the MINIMUM starting point which one is not allowed to do less than.

Originally Posted by Jerry Peck

Can you do better than the codes? I would hope so ... the codes are MINIMUM requirements, they are the WORST one is legally allowed to do .

Codes are not 'good', 'better', or 'best', the codes are simply the MINIMUM starting point which one is not allowed to do less than.

Jerry no offence but I am not here to bash the codes. they are there for a reason and as a base to start from. not everyone can afford the high end stuff or do better or wants to. they also teach us this is a good baseline to shoot for and what is basically needed for safety and generally what is acceptable, they to me are not the be all and end all of what is acceptable. As to what is seen out there is not always up to code and there is tons of stuff which is not seen and might never be seen which is not up to code but still happens, and nuthing happens because of it. All I am really saying is not everything has a readily available code to enforce it sometimes you just have to say here is what I think is a good safety thing to do and the reason for it. If it is reasonable and makes sense you don't need to quote a code for it even if there is one or not. we are not code enforcement people, but we do want to make sure a house is reasonably safe for the average person to buy and enjoy with out major problems from the get go.

Jerry you have a lot of good opinions keep them coming!! they make us all think and maybe not agree but they are worth reading!!

Originally Posted by Bill Hetner

Jerry no offence but I am not here to bash the codes. they are there for a reason and as a base to start from. not everyone can afford the high end stuff or do better or wants to.

Bill,

Regardless how you want to word it, codes are ... the absolute minimum you are legally allowed to build to.

The codes, by their own admission and statements, are not 'good', 'better', or 'best', the codes are: (these are their words, not mine, underlining and bold are mine)
- R101.3 Purpose.The purpose of this code is to provide minimum requirements to safeguard the public safety, health and general welfare through affordability, structural strength, means of egress facilities, stability, sanitation, light and ventilation, energy conservation and safety to life and property from fire and other hazards attributed to the built environment.

they also teach us this is a good baseline to shoot for and what is basically needed for safety and generally what is acceptable,

Who is the "they" who are teaching you that the codes are a good baseline to shoot for? Whoever "they" are ... "they" are wrong. All "they" have to do is read how the code describes itself - see above.

not the be all and end all of what is acceptable.

"They" are teaching that the codes are "what is acceptable", and to that extent "they" are correct - the codes are the "minimum allowed", and, being as it is allowed, it is therefore 'acceptable'.

That does not in any way make the codes 'good', and certainly not 'better' or 'best', just "minimum" ... as the code itself says it is.

Jerry, "they" are the people who write the codes. not everyone out there is a lic contractor or someone in the know about codes. also something which was acceptable 50 years ago might need to be changed to current codes or simply allowed to just be as it is. really depends on the situation. Yes I agree the code are the min standard, but the average homeowner diy might not know or care what the code is as long as it works and no one get's hurt. If someone knows the code then they have a good baseline from which to work with and go from there. better best is something which goes beyond the standard codes. Yes the codes are minimum but legally and techincally they are there to provide a minimum standard which is safe and good. I draw the line at good. below good to me is no good and unsafe. "they" the code writers want what is basically good for everyone and meets basic safety standards. anything which is below that or is a safety issue needs to be noted and let the powers that be deal with it. as a home inspectors we do not have the power to make changes happen or enforce them, all we can do is advise to the best of our ability.

there are lots of diy people out there with good intentions but a baseline to which to start from is a good thing imo. that would be a code. going beyond and better and best of a code is something which is up to the person working on the project. a code is there for a reason to guide and imform some one of what is acceptable and what the standard is. going beyond it is something which is the better and best for the situation.

I do not do everything in life to code but I try to do things to the best of my ability and knowlage. if I see a code and use it or go beyond it good for me and those around me that benifit. codes are there to teach those who don't know what is safe and minimum and guide those who do know what is acceptable the minimum level they have to keep to. Reaching beyond the code is a better thing but we can't always do it or know what can be done. we are all at different levels of knowage and sometimes need to learn from other's mistakes as it takes too long to make them all ourselves I know teach is a strong word here but sometimes we have to learn somewhere and go from there.

imo

Originally Posted by Bill Hetner

not everyone out but the average homeowner diy might not know or care what the code is as long as it works and no one get's hurt.

Which in no way indicates the code is 'good', only that it is the "minimum", which is, as *I* have been saying - the absolute "minimum" one is allowed to construct something, i.e., the crappiest it is legally allowed to be.

If someone knows the code then they have a good baseline from which to work with and go from there.

No, they do not have a "good" baseline from which to work with, they do, however, have a "MINIMUM" which they are REQUIRED to meet and go forth from there.

Yes the codes are minimum but legally and techincally they are there to provide a minimum standard which is safe and good.

Incorrect.

Codes "are there to provide a minimum standard which is safe" at the "MINIMUM" level acceptable. There is no 'good' level in the "minimum" standard.

Previously I posted from the IRC, now I will post from the NEC:
ARTICLE 90 Introduction
- 90.1 Purpose.
- - (B) Adequacy. This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.

That in no way implies or states that following the NEC will provide a 'good' installation, only one which meet that "NECESSARY" for safety. In fact, that even goes on to state "but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use." - okay, explain to me what is 'good' about that.

Jerry You are quite the character!!

short answer the codes are good for the basic safety purposes. as to " but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.
" that would be better or best stuff

And yes your answers here are correct!! But once again I still have my own opinion respectfully of yours.

Matt, et al, volt-amperes is an expression of volts times amps, usually expressed simply as VA. It is found by multiplying the voltage times the amperage.

That being said, 300 VA (volt-amperes) means 2.5 Amps on a 120 volt line---300VA/120volts = 2.5Amps. Although not an exact equivalency to Watts in AC systems, the NEC does allow the interchangeability of VA and Watts for simplicity---besides the numbers (values) are usually so low that an exact conversion is immaterial.


Also, I believe that someone else in this thread asked about the conversion between Watts and BTUs. One watt equals 3.412 BTU. And, one-horsepower equals 746 Watts.


Amperage equals Watts divided by the voltage. If, using only one phase such as 120 volts use 120, and the line (phase-to-phase) voltage if using both phases from a single-phase source such as 120/240, or if using any two phases from a split-phase source such as any two-phases from a three-phase system such as 120/208Y, etcetera. (NO, this is NOT a two-phase voltage! A two-phase voltage source is an entirely different system. It is derived from a 5-wire, "quarter-phase" source.) Also, multiple the line voltage by 1.732 if you are using 3-phases from a three-phase system.


As for the original question posted by Marc M. concerning the necessity of a disconnecting means at the furnace: Yes, it is required. Reference Article 422.30, 422.31 (B) & (C, if using the 2011 NEC), and 422.34 for Unit Switches [box-cover units with plug fuses & On-Off switches] for disconnecting means.

And, as for using a cord-and-plug for a disconnecting means, furnaces fall into the "Central Heating Equipment" category---Article 422.12, which requires they meet Article 422.31 "Disconnection of Permanently Connected Appliances." I know of none that are listed for cord-and-plug applications. If someone else knows otherwise, please correct me.


Thank you

Originally Posted by Bill Hetner

short answer the codes are good for the basic safety purposes. as to " but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.
" that would be better or best stuff

Not sure where "but not necessarily ... adequate for good service" says that it is a 'good' level to start at, but ...

But once again I still have my own opinion

... you certainly do have a right to think as you want.

Regardless that the code themselves disagree with you, and say so clearly.