ECN Forum Forums Code Related Discussion NEC & other Code issues Split systems

Usually the units i have seen are powered separately.

Disconnect is needed for both.

In the type of system I am talking about the air handler has it's own separate feed. It does not connect to the outside condenser except for the low voltage control wiring. The manufactures instructions do not show a disconnect either. Now if this was a regular air handler in the attic, a disconnect would be required.

How about a breaker lock? Would that make it a "Lockable" disconnect?

Also there is no plug and cord for the unit I refer to.

P.S.
I just saw leland's comment on the 2nd page.
I agree with leland, that a disconnect would be needed for both.

OK I was confused by the "hang on the wall" part and assumed a mini/split. In a regular AC unit with separate line voltage feed I agree you need a disco. In fact, these may have a pretty hefty toaster wire heat strip in them. My condenser is something like 17a, the air handler is closer to 50 with the heat on. (10 kva heat), on a 60a circuit.
Since these usually get installed in the attic or in a closet there is always the argument about working clearance around the disco. For some reason they usually let that slide but get concerned about the one on the condenser. Never made sense to me.

Greg,

There are several types of split systems. This air handler is 220 volt 15 amp. separate feed and has no heating coil and has no disconnect switch built in to it. It acts just like a typical AH that would be in an attic, but it is mounted on the wall. This one happens to be in my house:


http://www.residential.carrier.com/interactive/ductfree.html

Or something similar to it. Except there is no heating coils. Would a lockable breaker count for the disconnect?

Harold, Are you a qualified person?

If so, I read that the breaker will do.

440.14 exception 1:

A) Or, Could this unit be termed a 'controller'?


A) 430.102(B)(2) Exception.

It's standard procedure around here to to install a receptacle for the AH. 9 times out of ten it's a 120V unit mounted in the attic. The HVAC guy puts a pigtail on his unit and it can be tested (or run for temp heat) with an extension cord if he gets his job done before I get there.

Another benefit is that the HO can also run it from an extension cord for troubleshooting purposes or by portable genny in an outage.

Falls under the keep it simple rule as I see it.

I suspect something like this:

http://www.minisplitsystems.com/cgi...S71&gclid=CMmKmvKZ85gCFQrFGgodk3Hz0g

Leland, that is the minisplit I was talking about. They have a low voltage air handler, fed from the condenser.
Harold is talking about an air handler with 240v 15a feed. I can't imagine why you need all that if there is no heat.
The blower is going to be a fractional HP motor.
If it is 1/8 or less then you can cite 430.81(A).
Talking about Harold's air handler, I still bet this air handler has a heat bay if it really has a 3.6kva (240a @ 15a)circuit requirement. That machine does need a disconnect within sight IMHO.

If you can see the breaker from the AHU, you don't need a disconnect. Otherwise, you need some form of disco, whether it's a plug or a $20 HVAC disco switch or what have you. This applies even if the unit has a built-in breaker.