Is a SSU switch required for a furnace?Or can it be cord and plug only.

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there are a bunch of threads on furnace shut offs - do a search for "furnace switch" and you may find your answer
 
The code requires a dedicated circuit 422.12. It also doesn't allow cords400.7 400.8. The SSU swich is required as a disconnect "in sight of" 422.31B, and the fuse probably to cover the requirements for a motor overload device 430-225 B1 since it is not known to the electrician if the furnace motor will have overload protection. I am guessing here. I have never really thought about it since I have always used them.
 
As for the cord connection of a furnace, we've debated that here before. That seems to be the ways you guys go it on the left coast, whether it's NEC compliant or not. I guess a few million cord and plug connected furnaces can't be all wrong. :confused:
 
Bottom line, Furnaces are not listed for "cord and plug" connection. You can run NM into them if it is supported correctly. If you look inside the cover on many of them you will see requirements like "13 amp circuit max." That kind of makes it tough to use a 15 or 20 amp circuit and a cord.
 
Bottom line, Furnaces are not listed for "cord and plug" connection. You can run NM into them if it is supported correctly. If you look inside the cover on many of them you will see requirements like "13 amp circuit max." That kind of makes it tough to use a 15 or 20 amp circuit and a cord.


How are they not listed?
 
I will check on this. I was taught to do it this way and never really looked into it. It seems to have always been accepted as the "means of disconnect" for furnaces in my area.

Most of the time I see it pass also, but like I said in my earlier post I have seen units that have a maximum allowed input of 13 amps, how do you meet this on a cord and plug that is on a 15 or 20 amp circuit ?
 
Take a look at the last sentence of this section of the "08"

422.16 Flexible Cords.
(A) General. Flexible cord shall be permitted (1) for the connection of appliances to facilitate their frequent interchange or to prevent the transmission of noise or vibration or (2) to facilitate the removal or disconnection of appliances that are fastened in place, where the fastening means and mechanical connections are specifically designed to permit ready removal for maintenance or repair and the appliance is intended or identified for flexible cord connection.

the code does list certain items as being acceptable for cord connections, Dish washers, garbage disposers, ranges, etc. other then that it is in the manufacturers spec.
 
Most of the time I see it pass also, but like I said in my earlier post I have seen units that have a maximum allowed input of 13 amps, how do you meet this on a cord and plug that is on a 15 or 20 amp circuit ?

How would you meet it with a 15 or 20 amp breaker? Got any 13 amp breakers for sale?
 
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