I have an 8-yr old Armstrong Ultra SX 80 forced air gas furnace with Honeywell controls. My blower runs, but the furnace quit lighting last night. I tried some diagnostics that I found on this site, and what I have so far is:
1) I don't smell much gas, but that's probably due to the good airflow/draft.
2) My vacuum line is clear with no condensation. The vacuum is fairly light, so I tested with manual suction. I can hear the pressure switch activating, but still no ignition.
3) I hear no click from the spark ignitor. With an OHM meter, I get resistance through the 'sense' wire to the ignitor, but no change in resistance through the 'spark' wire.
Is the ignitor a likely candidate ?
Model # GUJ125D14-1A
Ignitor tag: Honeywell 204470DB
Thanks in advance for any advice.
"The road to Hell is paved with progressive policies."
when was the last time you had it serviced?
it could be many things, including a cracked or perforated heat exchanger(which is not healthy for anyone).
save yourself some time and money and call a pro, not only to find the problem, but to ensure the safety and efficiency of your furnace.
check with neighbors and family for a referral.
sounds like abad diy vavle i had a couple go bad on that particular unit