Air Handling (electric furnace) Disconnect Means

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bphgravity

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Consider a typical residential air handling unit used in a single family home. (The unit employs supplementary overcurrent devices, a blower motor and heating elements.)

The NEC requires a disconnecting means for the unit. Which section is applicable for determining the location of the disconnecting means?

1. Section 422.30
2. Section 424.19
3. Section 430.101

The specific issue deals with a particular builder that installs the air handler in a closet inside the home. There is no adequate space for a disconnecting means inside the closet. The builder does not want the disconnecting means on the outside of the closet.

I feel the only option to provide a "unit switch", which the particular air handler is designed for this application or a locking device could be provided at the branch circuit panelboard in the garage. I feel this is permitted by Section 424.19(A)(2)(2).
 
Re: Air Handling (electric furnace) Disconnect Means

424.19

[ January 10, 2005, 07:00 PM: Message edited by: dillon3c ]
 
Re: Air Handling (electric furnace) Disconnect Means

If it is 30 or less i have used a 2 pole toggle switch mounted insise wall.Here they want the disconnect within 6 feet of unit.Not nec but mechanical code.We run into units in closets often and always managed to get a pull out in them
 
Re: Air Handling (electric furnace) Disconnect Means

Bryan
does the supplementary ocpd control the heat only or the entire unit?
Would you consider this a unit switch if it controls the heat only portion?


What do you need heat for in Florida? :D

Pierre
 
Re: Air Handling (electric furnace) Disconnect Means

I have also been refered to the "6 foot rule", however I have now determined that rule is no longer in effect with the new FBC. The mechanical code is the International Mechanical Code ehcih does not have that requirement.

These units are 5, 7, and 10 kW units.

There are 5 internal fuses that I suppose protects each component of the package unit. The manufacturer sells a breaker that mounts on the unit and disconnects all incoming ungrounded conductors.

The breakers cost around $40 where a breaker locking device is $2. The builder wishes to use these in place of any disconnecting means at the unit itself. I am just looking for second opinion.
 
Re: Air Handling (electric furnace) Disconnect Means

"What do you need heat for in Florida? "
Believe it or not we are not always at 76 or higher and have seen ice and i can remember it snowing a few times,like up to 1/16 of an inch
 
Re: Air Handling (electric furnace) Disconnect Means

I concur with Jim. I lived in Orlando for awhile and just found it too cold there so I moved back to SW Florida. Other than the occasional Category 4 Hurricane, you can't beat it. Shorts and t-shirts 350+ days a year.
 
Re: Air Handling (electric furnace) Disconnect Means

Bryan, don't forget the polluted aquifer. ;)

Roger
 
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