Arco-Aire Pressure Switch Issues

I have an older Arco-Aire furnace. I had an issue a couple years ago and this forum helped fix it then. I'm having another problem so I'm back!

It has been extremely cold around here lately, -10 to -15 for the last couple of days.

When I got home from work last night my furnace was showing pressure switch stuck open error. I watched the switch as the furnace fired and I can see the diaphragm move when the induced draft motor kicks on. It appears to be fine and the burner will fire. Shortly after the burner fires it shuts down the burner and gives me the error. I can see the diaphragm fluctuate as the furnace goes through the cycle. If I push the diaphragm back the furnace will stay running and when I let go runs for a bit but then always shuts down and gives the pressure switch error.

Does this seem indicative of a bad switch?

Could the extremely cold weather be causing this issue?

My switch has 2 hoses and I noticed the replacements only have one.

Any thoughts or ideas would be greatly appreciated!

My furnace is model GDH100A016IL.




Thanks,

Gary

 

After doing some searching here and on the internet, I narrowed down my problem.

I was skeptical my pressure switch was actually bad and reading several posts here confirmed. One post suggested checking for a blockage in the venting system. I was suspecting a blockage in the intake due to extremely low temps and heavy snow.

I opened up the intake side to draw in combustion air from inside the house and my problem went away! Now I just need to wait for it to warm up enough to thaw out the intake.

I am aware of the dangers of CO and the added risk of it getting into the house through the "unsealed" vent. I have a working CO detector and am keeping a close eye on it. As soon as it thaws I will reconnect the vent so it draws from outside.