I have a 2 yr old, 80% gas furnace with a 2-stage blower. I tried to
use a back-up generator to run it during a power outage - but I
couldn't get it to light. The generator is 3000 watts(4000 surge) I
changed the dead circuit from a single pole switch to a short pigtail
cord and connect to the generator with an extension cord.

All the cords are good, 12 ga, and the distance was only about 60'. I
disconnected all the furnace wires from the house wires and moved them
all to the pigtail....The igniter would click, but not light.

I'm told the problem might have been that I didn't connect the grounds
effectively. Is that reasonable?

You disconnected "all the furnace wires". How many wires are there?

wrote in message
oups.com...
I have a 2 yr old, 80% gas furnace with a 2-stage blower. I tried to
use a back-up generator to run it during a power outage - but I
couldn't get it to light. The generator is 3000 watts(4000 surge) I
changed the dead circuit from a single pole switch to a short pigtail
cord and connect to the generator with an extension cord.

All the cords are good, 12 ga, and the distance was only about 60'. I
disconnected all the furnace wires from the house wires and moved them
all to the pigtail....The igniter would click, but not light.

I'm told the problem might have been that I didn't connect the grounds
effectively. Is that reasonable?

I also have an American Standard 2 stage, and just had a power outage
last week and was able to hook the furnace to my small generator.
Although after taking off the switch and seeing how many pigtails were
connected, I connected to the wire coming into the switch and
everything was fine. So I'd make absolutely sure that all the pigtails
were connected properly.

I'm not an AC guy, but I think there were 2 transformers hooked up to
this circuit. I'd guess it's to power the thermostat.. If there are
any HVAC pros out there, you can clarify.

I'm sure you already checked, but have to checked to make sure the gas
is on? Did the fan run?

Good luck.
tim1198

wrote:
I have a 2 yr old, 80% gas furnace with a 2-stage blower. I tried to
use a back-up generator to run it during a power outage - but I
couldn't get it to light. The generator is 3000 watts(4000 surge) I
changed the dead circuit from a single pole switch to a short pigtail
cord and connect to the generator with an extension cord.

All the cords are good, 12 ga, and the distance was only about 60'. I
disconnected all the furnace wires from the house wires and moved them
all to the pigtail....The igniter would click, but not light.

I'm told the problem might have been that I didn't connect the grounds
effectively. Is that reasonable?

That's why I asked the question I did. He should only have to deal with the
feed to the furnace, one cable, two wires + ground




wrote in message
ups.com...
I also have an American Standard 2 stage, and just had a power outage
last week and was able to hook the furnace to my small generator.
Although after taking off the switch and seeing how many pigtails were
connected, I connected to the wire coming into the switch and
everything was fine. So I'd make absolutely sure that all the pigtails
were connected properly.

I'm not an AC guy, but I think there were 2 transformers hooked up to
this circuit. I'd guess it's to power the thermostat.. If there are
any HVAC pros out there, you can clarify.

I'm sure you already checked, but have to checked to make sure the gas
is on? Did the fan run?

Good luck.
tim1198

wrote:
I have a 2 yr old, 80% gas furnace with a 2-stage blower. I tried to
use a back-up generator to run it during a power outage - but I
couldn't get it to light. The generator is 3000 watts(4000 surge) I
changed the dead circuit from a single pole switch to a short pigtail
cord and connect to the generator with an extension cord.

All the cords are good, 12 ga, and the distance was only about 60'. I
disconnected all the furnace wires from the house wires and moved them
all to the pigtail....The igniter would click, but not light.

I'm told the problem might have been that I didn't connect the grounds
effectively. Is that reasonable?

wrote:
I have a 2 yr old, 80% gas furnace with a 2-stage blower. I tried to
use a back-up generator to run it during a power outage - but I
couldn't get it to light. The generator is 3000 watts(4000 surge) I
changed the dead circuit from a single pole switch to a short pigtail
cord and connect to the generator with an extension cord.

The igniter may be sensitive to the polarity of the AC power line
relative to ground. Use a plug and receptacle to provide complete
isolation between the regular power system and generator. Are the
neutral and ground leads from the generator bonded together? This is
just one of many issues encountered when trying to tie a portable
generator into house wiring.