Complete repair guide for the Gulf Stream BT Cruiser – 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 Ignition Failure
Start by turning on your furnace and listening for the igniter click—if you hear nothing or the burner won’t light after 10-15 seconds, you’ve likely got a failed igniter electrode or control board issue. Use your digital multimeter set to DC voltage mode to test the 12V supply at the furnace control board connector; you should read between 11.5-13.5V with the furnace switch activated. Document which component fails the voltage test, as this will guide whether you need to replace just the igniter electrode or the entire circuit board.
Step 2: Disconnect Power and Propane Supply
Turn off the propane supply at your Gulf Stream’s main tank valve by rotating it clockwise until it stops, then flip the furnace breaker to the OFF position in your RV’s electrical panel. Wait at least 5 minutes before proceeding to allow any residual propane in the lines to dissipate safely. Verify power is completely off by attempting to activate the furnace switch—you should hear and see nothing.
Step 3: Remove Access Panel and Locate Components
Locate your furnace’s access panel, typically mounted on the exterior side wall or under a cabinet in your Gulf Stream, and remove the fasteners securing it. Once open, identify the furnace igniter electrode (a small ceramic rod with a wire connector near the burner assembly) and the control board (a rectangular circuit board usually mounted on the side of the furnace housing with multiple wire connectors). Take photos of wire positions and connector placements before disconnecting anything—this reference will be invaluable during reassembly.
Step 4: Disconnect and Remove the Igniter Electrode
Carefully disconnect the wire connector from the igniter electrode by gently prying the tab backward and pulling the connector free—do not yank or twist the wire itself. Remove the single fastener (usually a 1/4-inch nut) holding the electrode mounting bracket to the furnace, then slide the electrode out of its position. Inspect the removed electrode for visible cracks, carbon buildup, or a white ceramic tip that appears pitted; any of these indicate electrode failure.
Step 5: Replace Control Board and Connections
Disconnect all wire connectors from the old control board by documenting their positions, then remove the mounting bracket fasteners to free the board from the furnace housing. Install the new furnace circuit board in the reverse order, ensuring all connections match your photo reference exactly—incorrect wiring can prevent ignition or create safety hazards. Pay special attention to the sail switch connector and the 12V DC input lines, which are critical for proper furnace operation.
Step 6: Install New Igniter Electrode and Reassemble
Slide the new furnace igniter electrode into position (ensuring the ceramic tip points toward the burner area) and secure it with the mounting fastener, tightened firmly but not over-torqued—aim for snug resistance. Reconnect the igniter electrode wire connector by pushing it onto the terminal until you hear a small click, then verify it’s fully seated by gently tugging on the connector. Reinstall the furnace access panel and secure all fasteners, then reconnect the propane supply at the tank valve by rotating clockwise until hand-tight.
Step 7: Test Ignition and Verify Safe Operation
Reactivate the furnace breaker and turn on your furnace switch, listening carefully for the igniter click followed by a steady burner flame within 10-15 seconds. Use your digital multimeter to confirm the control board is receiving proper 12V DC power, and check that the sail switch closes when airflow is present (you should hear a subtle click). Finally, turn on your propane/CO combo detector alarm and allow it to run for 2 minutes to confirm no propane leaks or carbon monoxide are present—if any alarm sounds, immediately shut off the furnace and inspect all connections.