610 Combustion fan motor speed fault

What the control is telling you

Actual fan speed differs from the target speed set by the board, or fan speed is too low (≤20 Hz) or too high (≥500 Hz).

Applies to: I-Series Plus boilers — 150K BTU and smaller and 175K BTU and higher (Combi and Solo)

Likely causes

• Loose, broken, damaged or wet fan wiring
• No drive voltage from PC Board
• Debris on blower wheel or fan not turning freely
• Check valve behind fan stuck closed
• Failed fan motor
• Failed PC Board

Test and repair steps

1. Warning: Turn off power and gas before servicing the fan; never connect or disconnect the motor with power applied.
2. Inspect the harness from fan motor to PC Board for loose, broken or damaged connections, and make sure harnesses and connectors are dry.
3. While the unit tries to fire, measure at CN7: red pin #19 to black pin #18 should be 7–48 VDC (if none, replace PC Board).
4. At CN7, white pin #16 to black pin #18 should be 2–14 VDC, and yellow pin #17 to black pin #18 should be 11–14 VDC (if either is missing, replace the fan).
5. Remove the fan motor, check the blower wheel for debris and make sure it spins freely.
6. Make sure the check valve behind the fan is not stuck closed.
7. If windings are in spec and the fan turns freely but the fault remains, replace the fan motor.
8. If a new fan motor does not clear the code, replace the PC Board.