Rheem Criterion II won't ignite
I have a Rheem Criterion II that will not ignite the gas. Blower comes on, cycles through, and releases gas but the igniter never glows. I put a meter on the line for the HSI and the voltage climbs to 9VAC but never exceeds that amount. Pulled the HSI and gave it 120VAC from the wall. It glowed red hot. Checked the voltage at the pressure switch and it climbs to 24VAC for a short while and then drops to zero. Disconnecting the connector to the pressure switch and checking the voltage at the connector it remains at a steady 24VAC. I can manually light the furnace and it will run normally. Does anyone have any ideas here? How do I know if its the board? Is there another test for the pressure switch? Any help would be greatly appreciated.