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CHARLIE VAN FLEET
08-28-2008, 03:10 PM
hey all

inspection today and ac max fuse was rated at 35 amp. main panel breaker was 30 amp,but ac outside disco had a 60 amp breaker in it. a write up YES???
CHARLIE

Rick Cantrell
08-28-2008, 03:19 PM
You say the breaker in the house that controls tha A/C is 30a
But at the A/C disconnect it's a 60a

No problem

(I'm waiting for the slap on the head):)

Victor DaGraca
08-28-2008, 04:18 PM
The A/C is protected by the interior 30 amp breaker.
The exterior disconnect is just that, a disconnect,
Most A/C disconnects that I see have a blade type disconnect that pulls out and can be re-inserted backwards without making electrical contact.

Some are even "throw" handles either on or off.

CHARLIE VAN FLEET
08-28-2008, 04:35 PM
VICTOR
thats what i usually see the blade pull out fuses. i have never seen a breaker there before and such a high amperage
thanks
charlie

imported_John Smith
08-28-2008, 04:38 PM
I have been seeing a lot lately rated at say 35 amps max per manufacturers label, but with a 40 amp fuse in the main panel.

CHARLIE VAN FLEET
08-28-2008, 04:52 PM
john
thats not right!! i always write that up as" ac overfused". but this 60 breaker is the first i've seen
charlie

Jerry Peck
08-28-2008, 05:26 PM
Rick and Victor are correct in that the lower amperage breaker in the house panel protects it properly.

Regardless where the lower amperage breaker is, it will protect it properly.

Here is another thing to consider too: That ac disconnect is most likely not a breaker (does not offer any overcurrent protection), but is simply a "molded case switch".

They take the cases used for breakers and stick "disconnect switches" in them, but no overcurrent mechanism.

I tried zooming in on it, and it looks like is says "Molded Case Switch" in the second line down on the left side. It's too fuzzy to read when zoomed in that much, but I know what it most likely is and the fuzziness 'looks like it says that'. :cool:

Looks like it says:

2 Pole Type CP
Molded Case Switch
Listed ????
?????? UL
(can't make any more out)

Jim Luttrall
08-28-2008, 08:29 PM
Yep, that looks like the standard disconnect switch, no over current protection. That is a very common disconnect switch arrangement here. Of course we see more central A/C than you guys in the more temperate climates. I can't remember the last house I inspected that did not have central a/c.
The breaker at the main panel will be the over current protection.

Jerry Peck
08-28-2008, 08:40 PM
Fritz,

I was reading the writing on the breaker itself.

But I was cheating ... I knew what I expected it to say. :D

I also 'think' that next line down that I can't read says something like '10,000 A.I.C' before the UL symbol.

Below that, I'm not remembering what should be there, so it is all just fuzzy 'something'.

Paul Johnston
08-29-2008, 05:32 AM
Very good Jerry,
If it is just a switch why does it have a 60 amp rating. I am also surprised the NEC allows look alike equipment. Someone with much less vision than Jerry (like me) could confuse that for a breaker.

Jim Luttrall
08-29-2008, 05:55 AM
I'm not Jerry, but somewhere on the switch it usually says something like "no overcurrent protection", usually on the face. I think the UL sticker on the one pictured says "misc. switch". When installing, there is no doubt that it is just a switch.
The 60 amp is the rating of the switch, just like a duplex outlet is rated for 15 or 20 amps depending on the construction.

Billy Stephens
08-29-2008, 05:56 AM
Very good Jerry,
If it is just a switch why does it have a 60 amp rating. I am also surprised the NEC allows look alike equipment. Someone with much less vision than Jerry (like me) could confuse that for a breaker.
.
Good morning Paul,

I kind of look at it like a lighting fixture rated at a maximum 100 watt that can safely burn a 60 or 75 watt bulb. :)
.

Jerry Peck
08-29-2008, 07:24 AM
If it is just a switch why does it have a 60 amp rating.

As Jim (and Billy) said, that's just the maximum rating of the switching mechanism and its contacts.


I am also surprised the NEC allows look alike equipment. Someone with much less vision than Jerry (like me) could confuse that for a breaker.

Paul, you are not admitting that you don't read what it is that you are going to install, are you? ;)

Many times I've installed fixtures in our house and my wife (who happened to read the box which said 60 watt maximum wattage in large print on the picture of the fixture) asks 'Why are you putting 100 watt bulbs in there, it says 60 watt maximum?' :D

Paul Johnston
08-29-2008, 09:29 AM
No I'am not saying I don't read it its just that big brother is always trying to protect us from our self. A untrained person could instal it like as a 60apm breaker. That is way they changed the old screw in fuses to keep them from being inter changeable.

Jerry Peck
08-29-2008, 09:47 AM
A untrained person could instal it like as a 60apm breaker. That is way they changed the old screw in fuses to keep them from being inter changeable.

Actually, that is a bad analogy.

To fit that analogy, all breakers of different ratings would not be interchangeable into the same breaker space. I.e., you would not be able to install a 30 amp breaker where a 15 amp breaker would fit. :eek:

Now that would *really screw up* panelboards as we know them. :)

I do understand what you are saying, though. Mr. Average Joe Homeowner goes down to the Big Box store and Mr. Unknowing Salesperson direct Joe over to Aisle 14, down by the end, on the left side, where Joe picks through the breakers and pulls out a molded case switch because the molded case switch is in the wrong place.

Yeah, with those set of events, that could happen. But so could lots of other *bad things*.

The code does not, cannot, protect against unknown stupid people tricks 'just because someone might do something'.

You think the code is to complicated now, you would have to carry around a 32 volume set, like Encyclopedia Britannica, one volume address different 'stupid people tricks' and why you are not allowed to 'use this' under 'those conditions'.

Dan Hagman
08-29-2008, 11:14 AM
Rick and Victor are correct!:) Just remember Charlie, the outside is a service disconnect only(Service Disconnect for the HVAC Tech) as long as the interior main service panel has the proper size breaker and wire size, the condenser, and wiring, are protected properly.

ProSite Home Inspections
Altoona, Iowa
Dan Hagman

Gary Cox
01-03-2009, 10:22 AM
All of this talk of getting the breakers and fuses correct means nothing unless you determine that the wiring/cable feed to the unit is the correct size.

Jerry Peck
01-03-2009, 12:12 PM
All of this talk of getting the breakers and fuses correct means nothing unless you determine that the wiring/cable feed to the unit is the correct size..

Gary,

Please explain what the correct size is.

Is it:

a) The conductor size rating equal to or greater than the overcurrent protection rating?

b) The conductor size rating specified on the nameplate without regard to the overcurrent protection rating versus conductor rating?

Jeff Remas
01-03-2009, 05:51 PM
How about a photo of the AC units data plate. That is where all information for the answers are.

It should not be a problem but depending on the data plate, it can be.

If it is not a fused disconnect and just a disconnect and fuses are not required then not a problem. Some AC units require fused protection.

Is the breaker properly sized?
Are the conductors properly sized?

Need the data plate information.

Eric Shuman
01-04-2009, 07:08 AM
When I blew up the photo I can make out the very last printed line on the lower left side of the switch. It says, "Warning this device provides no overcurrent protection". I see this type of switch a lot in my area.

Eric

Wayne Carlisle
01-05-2009, 01:35 PM
They don't make a circuit breaker for the service disconnect. Even though it definitely looks like one.

I find a lot of oversized breakers in the panel box when AC units are changed out. The newer units don't require as large of a breaker as the older units.

Jerry Peck
01-05-2009, 01:37 PM
They don't make a circuit breaker for the service disconnect..

Actually, they do "make" one, its just that no one uses one there as the overcurrent protection is back at the panel and all that is needed is a simple "disconnect", no overcurrent protection needed there. So why spend the money?

Wayne Carlisle
01-05-2009, 01:45 PM
Really? Wasn't aware of one! But then again I don't know everything! Almost everything but not all!;)