Complete repair guide for the Forest River Solera – Furnace Igniter & Control Board Replacement. Follow these steps to diagnose and fix the issue yourself.
Parts & Tools You’ll Need
- Suburban RP-35Q 35,000 BTU/h RV Replacement Core for Suburban Furnace Series SF-35, SF-35Q, SF-42, SF-42Q, and SF-Q (2609A) — Suburban/Atwood RV furnace (replacement unit)
- Fit For Suburban RV Furnace Parts 232286,Single Probe Gas Furnace Igniters Electrode with Wire Assembly, Camper Furnace For Suburban 232286 Above 934701426 SF-20, SF-25, SF-30, SF-35 (SF Series) — Furnace igniter electrode
- DTAIR 33082 Sail Switch Replacement for Select Dometic Atwood RV Furnace(Pack of 2) — Furnace sail switch
- 520814 Rv Water Heater Module Board Ignition Control Circuit Board Compatible with Suburban Furnace SW4D, SW6D, SW6DE, SW12D, SW6DEM RV Water Heaters,Replace 520814 520820 520871 33550L (With lid) — Furnace circuit board / control board
- DTAIR 33082 Sail Switch Replacement for Select Dometic Atwood RV Furnace(Pack of 2) — Furnace high-limit switch
- Suburban 232684 RV Furnace 12v SF-Series DC Blower Motor, SF-35, SF-35F, SVF-35, SF-42, SF-42F OEM Caliber — Furnace blower motor (12V DC)
- RV Carbon Monoxide & Propane Gas Alarm, Briidea Dual LP/CO Detector with Separate LED Indicator Light, 100dB Loud Alarm, 12 VDC, Black — Propane/CO combo detector alarm
- FKM Pro Digital Multimeter Tester TRMS 6000 Counts,Smart Rechargeable Voltmeter 5″Color LCD,Auto-Ranging Automotive Multimeters,for AC/DC Current/Voltage,NCV,Ohm,Capacitance,Resistance,Continuity,Temp — Digital multimeter
Step 1: Diagnose Furnace Failure and Prepare Workspace
Before starting any repairs, verify that your furnace isn’t producing heat by checking that the thermostat is set to heat mode and the temperature is set above the current ambient temperature. Listen for the blower motor running and check whether you hear clicking or sparking sounds from the furnace compartment—these indicate igniter or control board failure. Disconnect the 12V power supply to your RV’s furnace system at the main battery disconnect or dedicated breaker, and allow the furnace to cool for at least 30 minutes before proceeding with any work.
Step 2: Access Furnace Components and Remove Control Board
Locate your Suburban/Atwood furnace unit, typically mounted in a basement compartment or under a cabinet in your Forest River Solera. Remove the furnace access panel by unscrewing 4-6 fasteners, then take a photo of the wiring configuration before disconnecting any components. Carefully unplug the furnace circuit board control board from its connector and remove it by unscrewing the mounting bracket—note that some models use a clip-style retention system rather than screws.
Step 3: Test and Replace Furnace Igniter Electrode
Using your digital multimeter set to the resistance (ohms) setting, test the igniter electrode by touching one probe to the electrode tip and the other to its mounting bracket; a healthy igniter should read between 40-90 ohms. If the reading is outside this range or infinite (no continuity), the igniter electrode has failed and must be replaced. Disconnect the igniter electrode connector and unscrew the mounting bracket, then install the new furnace igniter electrode by reversing the process, ensuring the ceramic insulator is clean and undamaged.
Step 4: Inspect and Verify Furnace Sail Switch Function
Locate the furnace sail switch, a small blade-activated switch typically positioned in the furnace air pathway that detects blower motor airflow. Manually move the sail switch blade by hand to confirm it clicks audibly and moves freely without binding; if it’s stuck or won’t click, replacement may be necessary. With your multimeter set to continuity mode, test the switch by checking that it shows continuity when the sail is pressed and no continuity when released.
Step 5: Install New Control Board and Reconnect Wiring
Take your new furnace circuit board control board and insert it into the mounting bracket, securing it with the fasteners you removed earlier or using the clip retention system. Reconnect all wiring harnesses to the new control board, matching each connector to its corresponding port and ensuring connections are fully seated with an audible click. Cross-reference your photo from Step 2 to confirm that the thermostat wires (typically red, white, and black), blower motor lead, and sail switch connection are properly attached to their correct terminals.
Step 6: Test High-Limit Switch and Verify Propane/CO Detector
Use your multimeter to test the furnace high-limit switch by setting it to continuity mode and confirming the switch shows continuity at room temperature (it should only open at dangerously high temperatures around 190°F). Check your Propane/CO combo detector alarm to verify it has fresh batteries and no fault codes or warning lights are displayed, as a malfunctioning detector could prevent your furnace from operating safely. If the detector shows a low battery warning, replace the batteries immediately—the furnace will not operate without a functioning propane detection system in your RV.
Step 7: Restore Power and Conduct Full System Test
Reconnect the 12V power supply to your furnace system at the main battery disconnect or dedicated breaker, then set your thermostat to heat mode and raise the setpoint 5 degrees above the current ambient temperature. Listen for the blower motor to start within 5-10 seconds, followed by the click of the igniter electrode igniting the propane burner; the furnace should produce warm air through the vents within 30-45 seconds. Allow the furnace to run on the heat cycle for 10 minutes, then monitor the furnace for any unusual smells, sounds, or unexpected shutdowns, and verify that the Propane/CO combo detector does not alarm.