I have a Weathermaker 8000, Model # 58zav096 -16. For the last week or so it has had intermittent ignition problems, sometimes it lights up, sometimes it fails.
When it fails the indicator light shows a 31 error. The manual -
PRESSURE SWITCH DID NOT CLOSE OR REOPENED - If open longer than five minutes, inducer shuts off for 15 minutes before retry. Check - - Excessive wind
- Proper vent sizing
- Defective inducer motor
- Low inducer voltage (115VAC)
- Defective pressure switch
- Inadequate combustion air supply
- Disconnected or obstructed pressure tubing
- Low inlet gas pressure (if LGPS used) - Restricted vent
If it opens during blower on-delay period, blower will come on for the selected blower off-delay.
Every time the furnace fails to light up, I find that the "Blocked Vent Safeguard Switch" has tripped. If I reset the switch, the furnace will fire up, then trip the switch again several hours later. None of the 6 causes above apply. I have taken the pressure switch out and it appears to work just fine. The furnace has not been serviced (cleaned) for 10 years.
Do I need to replace the "Blocked Vent Safeguard Switch" or what