What is the Residential AHU Whip Length

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Emtziii

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Texas
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Elecrician
Coming from the disconnect, in a residential area, how long of a run can I have? I'm being told, we're allowed 6 ft. I must disagree. The disconnect may have to be but, when romex comes out of the disconnect, it must be run in a way to protect it. That, usually means more than 6 ft. Am I weong
 
Emtziii said:
Coming from the disconnect, in a residential area, how long of a run can I have? I'm being told, we're allowed 6 ft. I must disagree. The disconnect may have to be but, when romex comes out of the disconnect, it must be run in a way to protect it. That, usually means more than 6 ft. Am I weong
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Without an installed equipment ground lfmc and fmc is limited to 6 ft. but if you pull a equipment ground in it you can be as long as you need it to be.
 
Emtziii said:
Coming from the disconnect, in a residential area, how long of a run can I have? I'm being told, we're allowed 6 ft. I must disagree. The disconnect may have to be but, when romex comes out of the disconnect, it must be run in a way to protect it. That, usually means more than 6 ft. Am I weong
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Welcome to the forum.

Are you talking about the main service cable? After the main OCPD, there's no limit.
 
This is for a residental air handling unit? You're making a whip with NM cable from the disconnect to the unit? I'm assuming that this is indoors.
 
LarryFine said:
Are you talking about the main service cable? After the main OCPD, there's no limit.
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Sorry, I missed the thread title. The length limit is for use as an EGC. Run one and you're okay.

The line-side's incoming Romex (shouldn't be outdoors) has an EGC, so that length doesn't count.
 
Are you sleeving the NM in Carflex outside? NM cable can't be used outside in any type of wiring method. Outside and UG conduits, raceways are subject to moisture and condensation, IE a wet location. NM is not allowed in a wet location. The conductors inside are not THHN so you can't strip off the jacket.
 
LFNC is a typical whip material for residential. LFNC-B can be any length if properly secured and supported per 356.30. Any other type (-A or -C) is limited to 6' lengths.
 
This time, I missed AHU. Wow. 🙄 I guess I'm more tired than I thought.

infinity said:
Can't an air handler just be wired with NM cable?
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Yes, as long as you physically protect it where needed. We usually sleeve it with FMC like a water heater or disposer.
 
We have an inspector here that won't allow LFNMC longer than 6' for a whip to an outside condensing unit. He states the support limit of 6' for it. He says "it's not supported swinging in the air or dragging the ground". I get it when in excessive lengths, but he won't allow an inch over 6' without adding some type of support.
This sounds like what the OP is talking about even though he said AHU.
 
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