Janitol furnace dilema

[bortos]

I am working on a 1993 Janitriol model number GMPN100-4. Actually two of them in the same residence. Big ranch house with on on each side.

I watch the Ignitor turn on, the main valve opens, it ignites and stays

lit for about 5 seconds, then the flame goes out. It waits about 30 seconds then does the same thing again.

It stops after three tries and then I get a single blink from the control board.

At least I think it is a single blink. It blinks on, waits 1/2 a second then blinks once again, repeat.....

I replaced the flame sensor and it still does the same thing.

Reading the sticker in the furnce, a single blink means Gas flow, Gas pressure, Gas valve, or Flame sensor.

Sure seems like it is the flame sensor to me, but I have swapped it out

once.

It wouldnt flame on if it was the Gas flow, Gas pressure or Gas valve would it?

Any Ideas?

Thanks in advance..

[dpb]

bortos wrote: ...

...

...

Flow and/or pressure would be first two since appears to not be sensor or valve.

Certainly it can initially light on low pressure or flow but not stay lit. Particularly would indicate this isn't sensor if (as I surmise altho you don't say so explicitly) both units are behaving the same way--the supply is common-mode, the sensors would require multiple identical failures...

[bortos]

Only one of the furnaces is malfunctioning.

Each furnaces has a sperate feed from different propane tanks.

And pressure was checked not to long ago when the tank on the "BAD" side was topped off.

Also, it has a new thermostat.

[Speedy Jim]

Swap the control boards.

Jim

[dpb]

Speedy Jim wrote: ...

and clean the orifices.

[cornytheclown]

Make sure all valves are open..at the tank on the gas valve in the furnace and the shutoff outside the furnace...after that if it doesnt work then call someone who knows how to work on gas furnaces....you obviously dont and while I commend you on trying to fix your own furnace there is a good chance that you could cost yourself more money in the end by damaging something. You could also endanger your families lives by messing with gas.

[dpb]

bortos wrote: ...

Where? At the tank, after the regulator, or at the furnace? One doesn't imply the latter necessarily if there's a problem in between...

[KAubert (Air-Care)]

[KAubert (Air-Care)]

check the polarity on power feed.

Hi all. First time on since we were KO'd by Katrina 13 mo. ago. We were down but not out.

MFEMF Air-Care

bortos wrote:

[bortos]

Thanks Jim,

Yea,

It was the control board.

I was convinced it was a polarity problem or a flame sensor positioning problem, but as soon as I swapped boards the other furnace had the problem and the other was fine.

Sometimes you just have to be reminded to do what should be the obvious, so,

THANKS MUCH