ECN Forum Forums General Topics of the Trade General Discussion Area Re: HVAC

"Technically it works, but if the AHJ asks if the 2-pole breaker is intended, and UL Listed, to protect a line-to-neutral load you may have a tough time answering."

What? With the NEC requiring multi-wire branch circuits to all trip together, it's impossible to argue that any multi-pole breaker is NOT approved for line-to-neutral loads.

Not sure how the GE product is wired, but unless you pull another complete circuit for the GFCI, I'd say it sure sounds like they're putting a receptacle on a circuit that serves fixed equipment. I can't imagine UL listing something prohibited by code.

I'll have to look at 210.23(A)(2). Considering all the gas appliances that use a simple cord & plug to feed their igniters, fans, etc., I again have a problem with an overly broad application of this idea.

I addressed 210.23(A)(2) a couple days ago.
If the FLA of this condenser is 10a or less it would be OK.
That could be true of a small mini split.

Would you apply any load calculation whatever to a service receptacle?

I have an issue with considering, say, the HVAC guy's vacuum pump as any manner of 'utilization equipment,' as it's not something ordinarily present. It's not as if it's a table lamp or something.

I deal with industrial roof fans and gas-fired space heaters daily. Finding a receptacle within even 100-ft is rare. On the roof? Get real- there's not a single receptacle in over 30 acres of roof! ANY trick that might let me have power at the work site is to be encouraged - not quibbled over.

I believe that the GFI in the disco box requires a 120 volt circuit to feed the GFI. That is for the very few I've seen.

A 240v circuit is a 120v circuit if they drag in a neutral.
210.4(C)ex2

Big B,

Sorry, I did mean the black and white, not the red wire. DUH! That is what happens when I type too fast and I don't think things through.

John,

This other AHJ I was talking to said that you can't put the receptacle on with the HVAC feeder. The receptacle would have to be a separate branch circuit. However he quoted sec. 440.3 which then referred him back to sec 430 (?) something which he said meant no it can't be done. I am trying to remember what section in 430 prevents the recpt. being on a multi-branch circuit.

John,

I have to go through sec. 430 to see what that other AHJ was talking about. Maybe I can call him on Mon. to see what code section he was revering to.

I think we're making more of this than needs be. We can eliminate all debate by simply trading one $20 item for another!

That is ... eliminate the HVAC disconnect. Instead, put in a 2-space / 4-circuit panel. Your wire is now a feeder, not a branch circuit.

The breaker can be used as a disconnect for the HVAC, and you have another two circuits available- say, one for lights and one for the service receptacle.

Harold I referred to that article 210.4(C) but ex2 says it is OK to have a L/L load on a multiwire circuit if you have a 2 pole breaker.

The biggest issue will be the FLA of the condenser. If it is more than 10, that is the deal breaker. You also have the problem that even a 10a condenser probably needs more than a 20a breaker to start reliably.

Reno has the answer. Run a slightly larger feeder and use a disconnect box with a panelboard that would handle both circuits.