FAU 20 amp requirement.

[Kg808]

Hey all. I hope this isn't a dumb question. But I don't do a lot of AC units or heating. I installed a receptacle for a new furnace in an attic for an AC/heating system. The name plate on the FAU/furnace read 8 amps. I ran a 20 amp dedicated circuit, as I normally don't do any dedicated equipment on 15 amps. But when speaking with the inspector I mentioned I might just use 14/2 and a 15 amp breaker on the next job, due to limited space available in the panel and a spare dedicated 15 A circuit was already in the attic. He said this was against code. And I was wondering which reference he may be referring to. He wasn't able to cite it. I am in CA. Maybe a CEC requirement?

Thanks for for your help!
I also found this forum. But didn't seem to help.
http://forums.mikeholt.com/showthread.php?t=98715

 

[infinity]

If the inspector failed to say why it was "against code" then it's anyone's guess what he was thinking. There is no NEC reason why you cannot use a 15 amp individual branch circuit.

 

[peter d]

I run 15 amp circuits to furnaces all the time. Rarely do they require more than 10 amps. Some large oil furnaces might require a 20 amp circuit due to the oil burner and blower motor. But gas? Never.

 

[Ponchik]

Where in CA? It will depend on your local jurisdiction. They may require a dedicated 20A.

Whether local or NEC requirement ALWAYS ask for a code reference. You are not trying to argue you just want to learn so when you relay the information to your co-worker you have a code section to back up.

I have had one inspector tell me "well that is what we require from the inspection office" but if it is not a written rule even within that inspection office then it is not enforceable.