Codes for the 903429 integrated control board

CONTROL LIGHT STATUS
RED
Steady ON Control OK
Steady OFF No power
Rapid Flash False flame or internal control fault
1 Flash Limit switch is open
2 Flashes Pressure switch is open with inducer on
3 Flashes Pressure switch is closed with inducer off
4 Flashes Lockout due to failed ignition
5 Flashes 115 vac & neutral reversed or no ground

YELLOW
Steady ON Good Flame Signal
Blinking Weak Flame Signal
Steady OFF No Flame Signal

M1M-Control Board Replacement

Replace the control board only after determining a failure has occurred in it. Most problems that are blamed on control are actually external to control. (See troubleshooting section). If control has failed, use the following procedure to replace.

1. Disconnect power to unit by turning off power switch.
2. Disconnect molex plugs and all push on terminal connections. Note connections for rehook up.
3. After all wire connections have been removed you must squeeze the four white stand offs to remove board. See Pictures 13 showing board removed with exposed standoffs remaining.
4. Carefully line up holes (Picture 12) on the new board over standoffs, and push into place. Caution: push from outside edge only - be careful of fragile components.
5. Reinstall all molex plugs and wires removed in step 2.
6. Apply power and re-test.