I have a 5 year old 90% efficient Heil Furnace. I get no response when I call for heat. (the "blower only" setting works fine.) I have confirmed that it is not the thermostat and that the fan control board has power. The gas valve light pulsates to indicate that it is OK. The lead that goes to the gas valve which then feeds the draft inducer motor has power going to the gas valve, but none coming from the gas valve to the draft inducer motor.

This leads me to believe that I have a problem with one of the limit sensors?

Any thought on this? Have I missed anything?

Thanks, Dan

Sounds like you may have tracked down the power problem. Best way is to test the sensors and if that is not it follow the low voltage line to find out what component is defective.

Thanks for the feedback. I tested the sensors. They checked out fine. I called in a technician to really check it out. Turns out my fan control circuit board was bad. I had a cracked internal drain hose which dripped water into the blower housing and onto the circuit board. Seems odd that those hoses would fail after only 5 years. Costly failure due to a cheap hose.

Many of the items on the furnace are made cheap now.