Every RV brand has a price point where the build quality starts compromising. I’ve bought rigs at every level, from entry-level travel trailers to high-end Class A coaches, and the failure patterns are consistent: manufacturers save money in the same places every time, and those are the systems that need attention first. On Forest River Cedar Creek units, the furnace is one of those systems — specifically the igniter and control board, which are spec’d just well enough to pass a factory inspection but not well enough to survive five seasons of real-world use. What makes this repair urgent isn’t just comfort; a furnace that fails to ignite properly can dump unburned propane into your living space, and a failing control board can send false signals that mask the problem until it’s genuinely dangerous. I’ve replaced this exact setup on multiple Cedar Creek builds, and this guide walks you through the diagnosis and swap the right way — no guesswork, no parts-store runaround.
Parts & Tools You’ll Need
- Suburban/Atwood RV furnace replacement unit
- Furnace igniter electrode assembly
- Furnace sail switch
- Furnace circuit board / control board
- Furnace high-limit switch
- Furnace blower motor (12V DC)
- Propane/CO combo detector alarm
- Digital multimeter (auto-ranging)
Disclosure: This post contains affiliate links. We may earn a commission on qualifying purchases at no extra cost to you.
Step-by-Step Repair Guide
Step 1: Diagnose Furnace Failure and Safety
Start by checking if your Cedar Creek furnace won’t ignite or produces no heat, indicating a potential igniter electrode or control board failure. Before beginning any work, turn off your propane supply at the tank, disconnect the negative battery cable, and ensure your RV is parked on level ground in a well-ventilated area to prevent carbon monoxide exposure.
Step 2: Access Furnace and Remove Panel
Locate your furnace unit, typically found in a basement cabinet or utility area beneath your sleeping quarters. Remove the furnace access panel by unbolting it from the mounting brackets, then carefully slide the entire furnace unit partially out to expose the control board and igniter electrode assembly.
Step 3: Disconnect Wiring and Propane Lines
Photograph the existing wiring connections with your phone before disconnecting anything, as this reference will prove invaluable during reassembly. Disconnect the propane supply line at the furnace inlet, the blower motor wires, the thermostat control wires, and any sail switch or high-limit switch connections using your multimeter to verify power is truly absent.
Step 4: Remove Old Igniter and Board
Unbolt the furnace igniter electrode assembly from its mounting bracket and carefully remove it, noting its exact position and orientation. Unscrew and remove the old circuit board by disconnecting its terminal block connectors and carefully sliding it out of its mounting slot.
Step 5: Install New Control Board Assembly
Slide the new circuit board into its mounting slot, ensuring it sits flush against the furnace housing and all terminal blocks align properly. Secure the board with its mounting bolts and reconnect all terminal block connectors according to your reference photo, double-checking each connection for proper seating.
Step 6: Install New Igniter and Reconnect
Position the new furnace igniter electrode assembly in its bracket, ensuring the electrode tip sits at the correct distance from the burner (typically 1/8 inch), then bolt it securely in place. Reconnect all propane lines using new brass fittings if the old ones show corrosion, then reconnect all electrical harnesses to the blower motor, sail switch, and high-limit switch.
Step 7: Test Ignition and System Function
Reconnect your battery, open the propane supply valve, and cycle your thermostat to call for heat while listening for the characteristic clicking sound of the igniter electrode sparking. Allow the furnace to run for 15 minutes, then check that the blower motor activates within 30 seconds and your propane/CO combo detector shows no alarm, confirming proper operation and safety.
Recommended Parts
| Part | Link |
|---|---|
| Suburban/Atwood RV furnace replacement unit | View on Amazon |
| Furnace igniter electrode assembly | View on Amazon |
| Furnace sail switch | View on Amazon |
| Furnace circuit board / control board | View on Amazon |
| Furnace high-limit switch | View on Amazon |
| Furnace blower motor (12V DC) | View on Amazon |
| Propane/CO combo detector alarm | View on Amazon |
| Digital multimeter (auto-ranging) | View on Amazon |