My furnace is either Bryant, Day & Night, or Payne. It is definitely model# 395CAV042091 Series E. It says "Plus 80" on front. Manufactured in 1995.
It had been working fine until today 3-Dec-2006. It stopped working. The component test works as expected (exhaust fan, igniter, blower). When the call for heat signal comes in, the exhuast fan turns on but the igniter, gas, and blower do not. After a short amount of time the status LED blinks a code 31.
I'm getting a status code of 31 - Pressure, draft safeguard switch or (some other) limiting switch (which my model does not have). After spending a lot of time checking all connections, waiting for presumed reset delays, and trial and error I disconnected the draft safeguard switch and got the same status code. As a test, I pulled both wires off of this switch and connected them together - shorted the wires together bypassing the switch. The furnace then worked fine. I suspect that this switch is bad.
1. Is it correct to assume that the draft safeguard switch is bad given the above information?
2. If so, how do I figure out where to buy a replacement switch? Using Google turned up a lot of hits but none of them dealt with buying a replacement switch.
Any advice would be appreciated.