Different brands fail in different ways — and once you’ve serviced enough of them, you start building a mental map of which rig is going to have which problem. That brand-specific pattern recognition is what separates a tech who’s been doing this for years from someone who’s just good with tools. The Forest River Riverstone is a luxury fifth wheel, and when I get a call about one sitting cold at a campsite in the middle of the night, nine times out of ten it’s the furnace — specifically a failed igniter or a fried control board that’s left the heating system clicking uselessly into the dark. What makes this repair particularly frustrating for owners is that the symptoms can look identical whether it’s the igniter, the board, or a combination of both, and misdiagnosing it means buying parts you don’t need and still waking up to a cold rig. I’ve done this repair more times than I can count on Riverstones specifically, so what follows is a straightforward, field-tested guide to diagnosing the root cause correctly and getting your furnace back up and running the right way.
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 Ignition Failure
Start by disconnecting the negative battery terminal to ensure your safety while working on electrical components. Use your digital multimeter to test the igniter electrode for continuity and verify that the control board is receiving 12V DC power from your RV’s battery system.
Step 2: Access Furnace Housing Assembly
Locate your RV furnace, typically found in a cabinet or under-floor compartment, and remove the access panel by unscrewing the mounting bolts. Document the position of all wire connections using photos or labels before disconnecting anything from the old furnace unit.
Step 3: Disconnect Propane and Electrical Lines
Carefully disconnect the propane supply line at the shut-off valve and cap the opening to prevent debris from entering. Disconnect all electrical connectors from the old furnace, including the 12V DC power lines, control board terminals, and blower motor leads.
Step 4: Remove Old Furnace Unit Completely
Unbolt the furnace mounting brackets from the RV frame using an appropriate wrench or socket set. Carefully slide the old furnace unit out of the housing compartment and set it aside for proper disposal.
Step 5: Install New Furnace and Components
Position your new Suburban/Atwood furnace unit into the housing and secure it with mounting bolts, ensuring it sits level and stable. Install the replacement igniter electrode assembly, sail switch, high-limit switch, and blower motor according to the manufacturer’s specifications provided with your new furnace.
Step 6: Reconnect Propane, Electrical, and Control
Reconnect the propane supply line and test for leaks using a soap solution around all connections. Reattach all electrical connectors to the new control board, blower motor, and sensor switches, matching your labeled connections from the old unit.
Step 7: Test System and Verify Operation
Reconnect your battery negative terminal and turn on the furnace to test ignition, flame establishment, and proper blower operation. Verify that your propane/CO combo detector activates correctly and use your multimeter to confirm 12V DC is reaching all components and that the igniter electrode is functioning properly.
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 |