furnace exhaust fan turns on... then the heating element lights up.... then the gas ignites breafly and then gas shuts off..then the fan stays on and it starts the process all over until it lights. most of the time it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.

diyme wrote:
furnace exhaust fan turns on... then the heating element lights up....
then the gas ignites breafly and then gas shuts off..then the fan stays
on and it starts the process all over until it lights. most of the time
it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.




Hi,
Two things to check; flame sensor and inducer pressure switch.
Sensor can have a fine surface rust causing intermittent operation,
switch can have a debris in the hose.

diyme wrote in message ...

furnace exhaust fan turns on... then the heating element lights up....
then the gas ignites breafly and then gas shuts off..then the fan stays
on and it starts the process all over until it lights. most of the time
it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.

The tech told me yesterday that the fan would always run, even if the
burner doesn't stay lit. Sometimes with mine, the fan would run for an
hour or so, blowing cold air, before it would light and stay lit. I
would only know that happened when it started getting warm in the house.
I'm having mine fixed in the next couple of days when the parts come in,
so if I learn anything about my problem, I'll post it and maybe it will
help you.

Cheri

I just went rhough this on my Amana furnace. Cleaning the flame sensor
did the trick and stopped it from going into lockout with the fan
running constantly.

Cheri wrote:
diyme wrote in message ...

furnace exhaust fan turns on... then the heating element lights up....
then the gas ignites breafly and then gas shuts off..then the fan stays
on and it starts the process all over until it lights. most of the time
it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.

The tech told me yesterday that the fan would always run, even if the
burner doesn't stay lit. Sometimes with mine, the fan would run for an
hour or so, blowing cold air, before it would light and stay lit. I
would only know that happened when it started getting warm in the house.
I'm having mine fixed in the next couple of days when the parts come in,
so if I learn anything about my problem, I'll post it and maybe it will
help you.

Cheri

wrote:
I just went rhough this on my Amana furnace. Cleaning the flame sensor
did the trick and stopped it from going into lockout with the fan
running constantly.

Cheri wrote:
diyme wrote in message ...

furnace exhaust fan turns on... then the heating element lights up....
then the gas ignites breafly and then gas shuts off..then the fan stays
on and it starts the process all over until it lights. most of the time
it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.

The tech told me yesterday that the fan would always run, even if the
burner doesn't stay lit. Sometimes with mine, the fan would run for an
hour or so, blowing cold air, before it would light and stay lit. I
would only know that happened when it started getting warm in the house.
I'm having mine fixed in the next couple of days when the parts come in,
so if I learn anything about my problem, I'll post it and maybe it will
help you.

Cheri

I just went through this too. The flame sensor, if it's like mine, is
a little rod that pokes into the flame area, with a wire connecting it
to the control module. You can see some by googling flame sensor so you
know what you're looking for. Apparently carbon buildup can make it
not operate correctly. Turn off power to the furnace and remove the
flame sensor, and clean the rod with some fine steel wool. The trick
here is thoroughness, go at it with the steel wool for like 15 minutes.
Good luck and post back if it works. -- H

Heathcliff wrote in message
.com...
I just went through this too. The flame sensor, if it's like mine, is
a little rod that pokes into the flame area, with a wire connecting it
to the control module. You can see some by googling flame sensor so you
know what you're looking for. Apparently carbon buildup can make it
not operate correctly. Turn off power to the furnace and remove the
flame sensor, and clean the rod with some fine steel wool. The trick
here is thoroughness, go at it with the steel wool for like 15 minutes.
Good luck and post back if it works. -- H

Thank you very much for the information. I will definitely look it up.

Cheri

Thanks everyone, I will give this a try and let you know if it works.

Tony Hwang writes:
diyme wrote:
furnace exhaust fan turns on... then the heating element lights up....
then the gas ignites breafly and then gas shuts off..then the fan stays
on and it starts the process all over until it lights. most of the time
it lights on the second time.
It does not do this all the time but more then we like.
Why is this happening?? Can we fix this or do we need to call someone?
Goodman installed in late 1998.

Hi,
Two things to check; flame sensor and inducer pressure switch.
Sensor can have a fine surface rust causing intermittent operation,
switch can have a debris in the hose.

I just went through a perhaps similar problem. Ended up being a problem with
the condensate drain lines. Combination of blockage in the line
leading from the ventor motor exhaust port to the trap and a slight
slope in the distal end of the condensate tubing just before it
entered the condensate pump. These combined to cause the inducer
pressure switch to shut off after condensate started
accumulating.

However, if problem is that the flame first shuts off almost
immediately but then burns properly for a sustained period the second
time, it probably is not a condensate blockage problem. Since
condensate blockage should build up more the longer the flame burns.