AC circuit breaker

I just love when Realtors question our observations.

I recently wrote this on an air conditioner compressor:

according to the manufacturer’s identification label, a 35 amp circuit breaker (see pictures) should be installed in the electric service panel for the air conditioner compressor unit. The circuit breaker in the electric panel attached to the air conditioner compressor appeared to be a 30 amp circuit breaker. Recommend that the circuit breaker be further evaluated by a licensed heating, ventilation and air conditioning technician.

This is what the listing agent emailed to me today:

My seller of XXXX was not pleased with the outcome of the inspection. The inspector asked for the A/C unit to be upgraded to 35 amps. The seller had an HVAC pro come out only to be told that it was already to code and not necessary to change. It cost him $126.00 for your inspectors mistake.

I emailed her that when we see this defect we write it up.

This was her next email:

I disagree with your assessment. The inspection objection asked the seller to install a 35 amp circuit breaker which was not needed. What was there was or is to code.

Just amazing how they want to run our business.

"I do not perform a Code inspection. I report on modern building practices and manufacturers recommendations. This manufacturer clearly states a 35 amp breaker should be used, hence my recommendation. "

Why do you suggest “further evaluation” when you know what the defect is? This sets you up to have to deal with an opposing opinion of someone whom you recommended come behind you and offer their " more expert opinion". Now you have to convince them that this more expert guy really wasn’t more expert and that they need to do it again. “Further evaluation” is for those few instances where they actually need a more expert opinion because you don’t have the answer.

Either just identify the defect and leave it at that or advise them to have it repaired by a qualified, licensed… In this case it would have been an electrician not an HVAC contractor.

Personally, I would think really hard before I suggested someone upgrade a 30A breaker to 35A on a 16 YO A/C unit if it wasn’t having starting issues.

Read the WHOLE label again.
What was installed at the external disconnect?

Condensers are labeled with Maximum fuse size. There is Nothing wrong with going smaller. I would mention the possibility of nuisance tripping, but a smaller breaker is not a defect. It is probably wired with a #10 wire, that is only rated for 30 amp.

Well first thing to note, HVAC installers are not licensed electricians, and I have seen them make mistakes more than once. Secondly, the code does not specifically dictate what size any particular air conditioning unit requires, that is on the unit plate by the manufacturer. The code only dictates how to calculate the conductor and breaker sizing, which has been done on the unit data plate. In this case, you were correct.

Well said.

I agree with Michael’s assessment, for whatever reason the manufacturer has stated that the OCPD must be 35 amps since that is both the minimum and maximum OCPD size. According to the listing of the unit that is the only size OCPD that could be used for this circuit. The fact that #10 conductors may be used is irrelevant because the conductors are sized according to the minimum circuit ampacity (MCA) which is 22 amps not the OCPD size.

Most modern units state the MCA and the maximum overcurrent protection device (MOCPD) size. In that case the conductors are sized according to the MCA and the MOCPD can be any size between the MCA and the MOCPD size.

The seller deserves a refund from the HVAC tech since he or she is incorrect.

And yet we know nothing of the OCPD at the external disconnect.

Would that matter if the circuit begins with a 30 amp OCPD that is too small?

Change the breaker bigger and what happens to the attached conductor?:-k

Nothing as long as the conductor is already sized for the MCA which in this case is 22 amps. A 22 amp conductor with a 35 amp OCPD would be code compliant.

And you know this because…?

All they are calling for is changing the breaker.
It could be 14ga. for all we know…

It could be but if the conductor is undersized then that is a separate issue. Since the OP merely stated that he called out that there was a 30 amp OCPD where the nameplate stated that a 35 amp was required one can assume that the original installation had the correct conductor size since no mention of it being too small was stated.

So assuming that the conductor is sized for 22 amp then the changing of the 30 amp OCPD to a 35 amp device will make the installation code compliant.

If that were the case, I would be calling for correction of the entire circuit.

According to the appliance, the circuit should already be sized for 35 amps.

This entire “ordeal” could have been avoided if the home buyer client understood basic, common sense “stuff.”

The original poster was right, 35amp breaker if that’s what the manufacturer recommends at maximum. Obviously, 30 amp is working fine. Case closed, move on.

Obviously the real estate person wants to start drama, and isn’t working on the benefit of their “client.”

Its a shame basic communication is lost somewhere between the lines, I’d definitely (if I was a Home inspector) remember this one.

So in your opinion the HI shouldn’t call out an incorrect size circuit breaker just because the one installed happens to work?

What am I missing here?
Wouldn’t the 30 trip quicker than the 35?

Duty ratings are not much different between that short spread.
I’d never write that up. If it is much over…Yes!

The issue is that the equipment, in this case an A/C unit, explicitly requires a 35 amp OCPD as per the nameplate on the equipment. The use of a 30 amp OCPD, although it may work, is a violation.

Whether or not an HI should call this out in a report is a matter for you HI’s to decide. :wink:

Regarding the OP, he’s being told that he was incorrect in his assessment of the installation by an electrician when in fact the HI was indeed correct according to the NEC.

Yes but as Robert Meier said for what ever reason the mfg. has indicted the breaker size must be 35 AMP

No wiggle room on this one if you follow the label.

I don’t recall seeing a label like this.

Typically it states the max O.C protection and minimum circuit ampacity

That is my opinion.

I see Robert and I cross posted. But I see it the same way as he does.