[Colton m]

I have a 80% Goodman furnace that won’t start. The inducer turns on then it shuts down because the pressure valve won’t close. If I suck on the tube I can get it to fire and start. Exhaust pipe clear.port for tubing clear. Do I have a bad pressure switch?

 

[roughneck]

Check the draft with a manometer.
Exhaust, tubing or the pressure switch may be clogged.
Should have more draft then the pressure switch is rated for at the pressure switch.
Could also be a sign of heat exchanger issues.

 

[Colton m]

Pressure switch clicks when I blow in or suck on the tube but the draft inducer would create less psi I believe. I had alot of condensation in the exhaust pipe. Possible water logged the pressure switch?

 

[roughneck]

You can rupture the diaphragm in the pressure switch by placing too much negative pull on it.
It will definitely damage it putting positive pressure on the diaphragm by blowing into it.
It could be clogged with water somewhere, yes.

 

[Colton m]

All right I appreciate it I’ll look into it after work would you suggest taking the pressure switch apart in order to inspect? Or just try replacing

 

[roughneck]

I’d check the draft before replacing unnecessary parts.
The pressure switch isn’t field serviceable.