Disconnect for gas furnace?

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ritelec

ritelec

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Jersey
Trouble shooting a lighting and receptacle circuit in a residence. Wiring neutral of one circuit to ground for return path from one end and gas furnace circuit hot from the other end ?? Long story short:
Question. Does the circuit breaker for the gas furnace in a panel in sight and 20 feet away satisfy requirements for the maintenance disconnect switch or do I need to install a switch on the unit itself?
Thank you
 
ritelec said:
Trouble shooting a lighting and receptacle circuit in a residence. Wiring neutral of one circuit to ground for return path from one end and gas furnace circuit hot from the other end ?? Long story short:
Question. Does the circuit breaker for the gas furnace in a panel in sight and 20 feet away satisfy requirements for the maintenance disconnect switch or do I need to install a switch on the unit itself?
Thank you
Click to expand...
Yes. It's 25'

Sent from my BE2028 using Tapatalk
 
Depending on your location, there may be additional requirements by a mechanical code.
Here is one:
(6) The disconnecting means shall be permitted to be a branch circuit breaker at the distribution panelboard, provided that the panelboard is located between the furnace and the point of entry to the area where the furnace is located.
(7) Where a separate switch is required due to the unsuitable location of the branch circuit breaker, it shall
(a) not be located on the furnace nor in a location that can be reached only by passing close to the furnace; and
(b) be marked to indicate the equipment it controls.
 
augie47 said:
Depending on your location, there may be additional requirements by a mechanical code.
Here is one:
(6) The disconnecting means shall be permitted to be a branch circuit breaker at the distribution panelboard, provided that the panelboard is located between the furnace and the point of entry to the area where the furnace is located.
(7) Where a separate switch is required due to the unsuitable location of the branch circuit breaker, it shall
(a) not be located on the furnace nor in a location that can be reached only by passing close to the furnace; and
(b) be marked to indicate the equipment it controls.
Click to expand...
Augie, are these requirements for a gas furnace?
 
As of now there's a 15 amp single pole switch in a hallway before the stairs leading to the basement. The switch was wired line and load to one screw so it wasn't switching the furnace. The furnace was always hot and the other screw to the switch was feeding a lighting/receptacle circuit.

It's an older switch and rather than opening up the unit to research the motor and replace the switch with a rated Hp switch, I am hoping to eliminate it and just use the breaker as the switch.
 
ritelec said:
As of now there's a 15 amp single pole switch in a hallway before the stairs leading to the basement. The switch was wired line and load to one screw so it wasn't switching the furnace. The furnace was always hot and the other screw to the switch was feeding a lighting/receptacle circuit.
Click to expand...
It sounds to me like the feed in should be moved to the other switch terminal, so the lighting/receptacle circuit is always hot, and the switch controls only the furnace.
 
LarryFine said:
It sounds to me like the feed in should be moved to the other switch terminal, so the lighting/receptacle circuit is always hot, and the switch controls only the furnace.
Click to expand...
See OP's post #8.
1. The existing switch may not be rated for switching the furnace and the OP does not have ready access to the motor information for the furnace.
2. The other circuit feeds lighting (presumably built in) and receptacles. Maybe switching the receptacles is not needed, but I do not think continuous-on ceiling lights would be acceptable to the customer.
 
The furnace should have it's own dedicated circuit.

Sent from my BE2028 using Tapatalk
 
I have the furnace on it's own circuit now.

Originally it looks like there was no neutral in a near by lighting/receptacle circuit so somewhere along the line someone hooked the neutral up to a ground in a three gang box a few rooms away. It also looks like that same lighting/receptacle circuit was never fed so they snaked a 3 wire from that furnace switch box (which is a dead end switch leg in on the white and back on the black) to one of the switch boxes with no power and used two conductors to feed the lighting/receptacle circuit from the furnace switch box at that location..... one conductor from the load side of the furnace switch feeding the light/receptacle circuit and one conductor from the line of the furnace switch feeding a switch in that box.

All the wiring seems to be correct now, but I'm not happy with the 15 amp existing furnace switch and was considering splicing and putting a blank on it and use the breaker as the disconnect switch.

The furnace is on a 15 amp circuit. I think I'm going to go with a 20 amp switch and swap the 15 amp switch to a 20.
Besides HP rating, I believe for certain size HP motors the switch can be rated twice the amperage of the motor. What are the odds that a furnace blower motor is going to be more than 10 amps?

Thank you.
 
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