outside ac unit

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Cooper Electrical

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hello all, I was on a job today doing some new air handlers and ac units . Its a commercial building and the air handlers are also heaters . We bought these disconnects for the ac units with gfi's already installed . So I bought 2 circuits into the disconnect. I was going to tie into the line side on the heater circuit anyone see a problem with it .... My boss said I couldnt do it because anyone that was working on would trip the breaker .... I think they would turn off the disconnect switch ....And if they did turn off the heater all you would lose besides the heater would be the gfi inside the disconect ...

so what do you think
 
I read that twice, and I'm having trouble following what you're asking. In short, with the disconnect(s) in the open position, any required GFCI's or receptacles need to stay hot.
 
rephrase needed

rephrase needed

Cooper Electrical said:
hello all, I was on a job today doing some new air handlers and ac units . Its a commercial building and the air handlers are also heaters . We bought these disconnects for the ac units with gfi's already installed . So I bought 2 circuits into the disconnect. I was going to tie into the line side on the heater circuit anyone see a problem with it .... My boss said I couldnt do it because anyone that was working on would trip the breaker .... I think they would turn off the disconnect switch ....And if they did turn off the heater all you would lose besides the heater would be the gfi inside the disconect ...

so what do you think
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Could you clarify the setup in more detail? Is the disconnect ahead of each of two paralleled airhandler and A/C units and if so why the GFI? Or did you mean A/C's with GFCI's? rbj
 
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ok .... i have a air handler in the attic with a disconnect switch 120 volt. my outside ac unit is 240 . I ran a emt from attic to the ac diconnect with a 240 circuit in it and a 120 volt circuit in it for a gfi that is in the disconnect. I wanted to come off the line side of the 120 volt air handler for my outside gfi ... any thoughts
 
Cooper Electrical said:
ok .... i have a air handler in the attic with a disconnect switch 120 volt. my outside ac unit is 240 . I ran a emt from attic to the ac diconnect with a 240 circuit in it and a 120 volt circuit in it for a gfi that is in the disconnect. I wanted to come off the line side of the 120 volt air handler for my outside gfi ... any thoughts
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I would read 210.23(A)(2). It's very probable that the air handler will draw more than 50 % of the load.

(2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord-and-plug-connected utilization equipment not fastened in place, or both, are also supplied.
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So, the question is, can the condesing unit 120v service recep come from the air handler circuit.

I say yes.....so it's probably no.

And.....the AH is likely not 50%. Generally 3ish amps.
 
220/221 said:
So, the question is, can the condesing unit 120v service recep come from the air handler circuit.

I say yes.....so it's probably no.

And.....the AH is likely not 50%. Generally 3ish amps.
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My memory of AHU is about 12 amps depending on the size. I just looked up a cheap online air handler and they varied from 8- 14 amps.
 
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