Here's my problem. York Diamond furnace, heat turns on but after running for a while, turns off with 6 flashes indicating pressure switch opened 5 times after normal operation. Here are some observations.
1. Pressure switch is about 2 years old.
2. The tube from draft inducer to the pressure switch is clean.
3. The pressure from the draft inducer to the pressure switch seems low.
4. I can hear the draft inducer running and it sounds pretty strong.
so I'm thinking either one of these.
1. Bad pressure switch
2. Bad draft inducer
3. Clogged vent.
My questions are as follows:
1. How much suction should I expect from the draft inducer to the pressure switch? I feel some suction coming from the inducer when it's on but it's not so strong. Should it be really strong like it's sucking air strong or should it be slight?
2. How do I verify if I have a clogged vent??
Your help is appreciated. Thank you!