Rheem Gas Furnace: R801

Re: No Ignition - No Fault Codes

The furnace control goes through an ignition sequence, but the gas valve does not open and there is no spark.

The furnace restarts after each failed attempt, but no fault is displayed.

CHECKOUT:

1. Check Control

• Check voltage between "W" and "C" at the control board.
  • 22 - 26 VAC → Step 2. Check Gas Valve
  • Less than 20VAC = Low Line Voltage or Mis-Wired Transformer
    • Check Inlet Line Voltage

2. Check Gas Valve

• Unhook the two low voltage wires (YL & BL) from the gas valve and re-try an ignition attempt.
• Check power between the YL & BL wires at the point of ignition.
  • Control Sparks and 24VAC Present = Shorted Gas Valve
  • No Spark & No Voltage = Bad Control Board