When the t-stat calls for heat, the fan starts and then after about 1 min. it stops. Control board shows diag2 flashing, diag 1 off - which indicates pressure switch opened due to reduced air flow or a blocked condensate drain.
When I remove the tube between the pressure switch and inducer(fan), I can blow on the tube to the pressure switch and it works. The inducer side port(nipple) is clogged completely. I tried to suck and pinch on the tube while starting the furnace, and it comes up so I know furnace is working.
I tried to clear the port with a paper clip, thin nail. But it won't go through. Seems to be solid clogged. I wanted to know should the paper clip go all the way through? Any suggestion on how to clear the port?
I also checked the vent to the roof and it's clear.