FAN 50 PLUS PINS 12V Universal Ignitor Board | RV Furnace & Water Heater

FAN 50 PLUS PINS 12V Universal Ignitor Board with Fan Control

The ignitor board is the ignition control module for your RV furnace or water heater, managing the ignition sequence, flame sensing, safety lockout, and (on fan-equipped models) combustion fan control. When the ignitor board fails, your furnace or water heater may fail to ignite, cycle on and off, or lock out completely.

This FAN 50 PLUS PINS universal 12V ignitor board is designed as a replacement for Atwood, Dometic, and Suburban furnace and water heater ignition control boards. It features built-in fan control, trial ignition timing, flame sensing, and safety lockout — all in a compact, easy-to-install module.

Compatibility

• Atwood Hydro Flame furnaces (85-IV, 89-III, AFMD series)
• Atwood water heaters (GC6AA, G6A-8E, G16-EXT)
• Dometic DFMD, DFSI series furnaces
• Suburban SF, NT, SW series furnaces and water heaters
• Most 12V RV furnaces with fan control and spark ignition
• Replaces board numbers: FAN 50 PLUS, 520814, 520820, 31501, 33488, 33727

Specifications

Installation Guide

1. Safety first: Disconnect 12V power at the battery. Turn off propane supply.
2. Access the board: Remove the furnace or water heater exterior access panel. Locate the ignitor board, typically mounted near the burner assembly.
3. Document connections: Take a photo of the wire connections. Note which wires go to which pins.
4. Disconnect wires: Unplug the pin connectors from the old board. Note the position of each connector.
5. Remove old board: Unscrew the 2 mounting screws holding the board.
6. Install new board: Mount the new FAN 50 PLUS PINS board in the same position. Secure with mounting screws.
7. Reconnect wires: Plug all pin connectors into the corresponding positions (refer to your photo). Ensure all connections are secure.
8. Test operation: Reconnect 12V power. Turn on propane. Set the thermostat to call for heat. Verify the ignition sequence: fan starts → spark ignites → flame is sensed → fan continues. Check for proper operation through at least one complete cycle.

Ignition Sequence

1. Call for heat: Thermostat closes, sending 12V signal to the board.
2. Pre-purge: Combustion fan runs for 15 seconds to clear any residual gas.
3. Trial ignition: Spark igniter activates, gas valve opens. Board attempts ignition for up to 8 seconds.
4. Flame sense: If flame is detected, spark stops, gas valve stays open, fan continues.
5. Retry: If no flame is detected, board retries up to 3 times.
6. Lockout: After 3 failed attempts, board locks out for 30 minutes. Manual reset (power cycle) required.
7. Post-purge: When thermostat opens, gas valve closes, fan runs for 30 seconds to cool the heat exchanger.

Common Symptoms of a Bad Ignitor Board

• Furnace or water heater won’t ignite — no spark
• Fan runs but no ignition
• Ignites but won’t stay lit (flame sense failure)
• Cycles on and off repeatedly
• No fan operation (if board controls the fan)
• Lockout after one ignition attempt (should retry 3 times)
• No response to thermostat call for heat
• Clicking sound from the board but no operation

Frequently Asked Questions

Q: What is the difference between PINS and WIRE versions?

A: The PINS version uses pin-style connectors that plug directly into the board. The WIRE version uses wire leads that need to be connected with wire nuts or terminals. This listing is for the PINS version. If your original board has wire leads, you may need the WIRE version or an adapter. Contact us if you’re unsure.

Q: How do I reset the board after a lockout?

A: After a safety lockout (3 failed ignition attempts), the board will remain locked for 30 minutes. To reset immediately, disconnect 12V power for at least 10 seconds, then reconnect. This clears the lockout and allows a new ignition attempt.

Q: Can I use this board in a water heater without a fan?

A: Yes. The fan control output is optional. If your water heater doesn’t have a combustion fan, simply leave the fan output unconnected. The board will still perform spark ignition and flame sensing normally. The pre-purge and post-purge timers will still run but won’t affect operation without a fan.

Q: What should the spark gap be?

A: The spark electrode gap should be approximately 1/8″ (3mm). Too wide a gap may prevent sparking; too narrow may cause weak spark. Check and adjust the electrode gap if you’re experiencing ignition problems.

Related Products

• 520820 Circuit Board with Fan Control — Atwood furnace replacement board with fan control
• 520814 Module Ignition Board — Atwood furnace ignition control module
• 31501 RV Furnace Ignition Board — Compatible with Atwood & Dometic Hydro Flame furnaces

Need help finding the right ignitor board for your furnace or water heater? Contact our technical team with your model number. Free shipping and duties included.