Furnace wiring + condensate pump


Old 09-22-07, 01:46 PM
JoeTheZombie's Avatar
Thread Starter
Join Date: Nov 2005
Location: Idaho
Posts: 216
Received 0 Votes on 0 Posts
Furnace wiring + condensate pump

My furnace specifies a maximum 15A circuit. The wiring from the panel is 12/2, and the breaker is 15A. I have a small (2A) condensate pump I wish to install. I would like to:

Change the 15A breaker to a 20A, install a receptacle in the furnace closet for the condensate pump, and install a 15A fused disconnect for the furnace with power from the receptacle.

This would keep the furnace on a max 15A, and also supply power for my condensate pump.
Sponsored Links
Old 09-22-07, 02:31 PM
Join Date: Sep 2000
Location: United States
Posts: 18,497
Received 0 Votes on 0 Posts
How many amps does your furnace need? Are you sure you need to go to all this trouble?
Old 09-22-07, 02:45 PM
JoeTheZombie's Avatar
Thread Starter
Join Date: Nov 2005
Location: Idaho
Posts: 216
Received 0 Votes on 0 Posts
The furnace ampacity is listed as 13.4A, and the max fuse or breaker must be 15A as indicated on the unit.

I need to install an outlet for the condensate pump, and doing it this way would let me use the existing wiring to the furnace rather than running a new circuit.

I read somewhere the NEC requires the furnace to be on a dedicated circuit, so that is where my concern stems.
Old 09-25-07, 10:15 AM
Join Date: Feb 2002
Location: port chester n y
Posts: 2,117
Received 0 Votes on 0 Posts
Convert the existing 20 amp Branch - Circuit to a "Feeder" by terminating the 12/2 conductors on the lugs of a 2-circuit panel .

DO NOT connect the EGC of the 12/2 cable to ANY Neutral terminations -- Bond a lug to the metallic surface of the enclosure , and connect all cable EGC's to the lug which "Bonds" together the enclosure and the EGc's .
Old 09-25-07, 10:53 AM
Forum Topic Moderator
Join Date: Sep 2005
Location: USA
Posts: 4,926
Received 54 Votes on 51 Posts
I'd suggest tapping power from some other circuit nearby (basement lights, garage receptacle, etc) as the condensate pump is generally quite a low draw. That way you don't have to worry about additional fuses or panels or such. Just install a simplex receptacle (non-GFI in my opinion) and have at it.

Just my suggestion.
Old 09-25-07, 11:06 AM
Ed Imeduc's Avatar
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 18,389
Received 0 Votes on 0 Posts

Might check code there. lot of codes now call for a dedicated circuit to the furnace. With a cut off switch at the top of the stairs to the basement.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: