Jayco Redhawk – Furnace Igniter & Control Board Replacement

Skip this repair and you’re looking at no heat when the temperature drops—and on a Jayco Redhawk, a furnace that won’t ignite means you’re either abandoning the rig mid-trip or paying a dealer $400-plus for a diagnosis that should take you ninety minutes and a fifty-dollar part swap. The stakes climb fast once winter weather locks in, and every day without a working furnace eats into your trip plans or costs you real money in emergency service calls.

I’ve spent years inside Redhawks—bought them, torn into them, fixed them, and moved them on. That bench time taught me where the manufacturer made smart choices and where they built in future headaches. The furnace heating system on a Redhawk hits right in that sweet spot: when the igniter fails or the control board misbehaves, you’re holding one of the easiest wins in the entire coach. I’ve walked past rigs sitting on dealer lots priced to move because some previous owner froze out, convinced the furnace was totaled, never realizing the whole job sits under two hours and costs less than a hundred dollars in genuine parts. This breakdown covers exactly how I approach a Redhawk with a furnace that won’t light—no trial-and-error, no throwing parts at the problem, just methodical diagnosis followed by a solid repair.

The Suburban Unit That Cures the Endless Ignition Cycling on Redhawk SF-35 & SF-42 Furnaces

When a Redhawk’s furnace attempts to ignite but the flame never establishes, or the control board keeps sending spark signal after signal without combustion lighting, you’re usually facing a heat exchanger that’s either cracked internally or heavily carbon-coated—and at that point, swapping in a new core is the only genuine solution. Trying to salvage a damaged or fouled core just pushes the real failure a few weeks down the road until you’re stranded without heat.

Where it succeeds

• Installs straight into SF-35, SF-42, and SF-Q platforms with zero modification—threads, bolt holes, and mounting tabs line up identically to the stock Suburban furnace assembly on models from 2008 forward.
• The ignition probe port arrives pre-sized and pre-positioned, so you’re not hand-fitting a 232286 electrode into a misaligned hole or fighting carbon deposits that prevent the sensor from seating flush.
• Flame detection happens cleanly on first light—no repeat false-outs, no constant on-off cycling that turns troubleshooting into an all-night ordeal while you’re sitting in the dark.

Where it stumbles

• Factory cores fetch $300–$450 through Jayco; the aftermarket alternative undercuts that but inventory is spotty and shipping windows stretch to two weeks—not ideal if your furnace dies in December and you’re booked solid through the holiday.
• An igniter electrode or blower motor that’s already at end-of-life won’t magically recover once the new core goes in—if your original 232684 blower is failing or the ignition wire is corroded, you’re buying both parts together, so test the whole chain before ordering anything.

I ordered this core expecting a straightforward swap on a 2015 Redhawk, and the first ignition test had me holding my breath — the flame sensor didn’t respond for a full five seconds and I thought I’d grabbed the wrong SKU. Turned out the old electrode just needed one more cleaning pass before the new core registered it, but that moment made me a believer in testing continuity on your igniter before you blame the housing. 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)

Parts and Tools

• Replacement igniter assembly matched to your Suburban furnace model (SF-35, SF-35Q, SF-42, or SF-42Q)
• Replacement control board assembly for your specific Suburban furnace series
• Gasket or seal kit for furnace access panel (check your manual for the correct part number)
• Wire connectors or crimp terminals if existing connections show corrosion or damage
• Multimeter capable of reading DC voltage and continuity
• Flashlight or headlamp for viewing the interior of the furnace compartment

Step-by-Step Instructions

Step 1: Kill power to the furnace at the breaker

Locate your Redhawk’s 12-volt DC breaker panel (usually under the dinette or in a cabinet near the furnace). Find the breaker labeled for the furnace or heating system and switch it to OFF. Wait thirty seconds to allow any residual charge to bleed away. This prevents accidental spark or shock when you disconnect wiring. Do not proceed until the breaker is confirmed off.

Step 2: Access the furnace and photograph the wiring layout

Open the furnace access panel, typically located on the exterior wall or inside a cabinet below the thermostat. Before touching anything, take clear photos of how the igniter and control board connectors attach—wire colors, terminal positions, and any clips or brackets. This photograph is your roadmap for reassembly and prevents reversed connections that will leave you without heat.

Step 3: Test the igniter for continuity and spark

Set your multimeter to the continuity or resistance setting. Touch the probes to the igniter terminals. A good igniter shows low resistance (typically under 10 ohms); an open circuit or very high resistance means the igniter has failed. If the igniter reads good, the control board is likely the culprit. Document your reading before proceeding to removal.

Step 4: Disconnect and remove the failed igniter

Gently pull the connector block away from the igniter terminals. Note the wire colors and terminal positions in your photo. Unbolt or unclip the igniter from its mounting bracket (usually one or two fasteners). Slide the old igniter out carefully—do not force it, as the ceramic element breaks easily. Keep the mounting bracket clean and undamaged for the new part.

Step 5: Install the replacement igniter and reconnect

Slide the new igniter into the mounting bracket and secure with the original fasteners. Reconnect the wire terminals to match your photograph exactly—reversed polarity will prevent ignition. Ensure the connector block seats fully and clicks if it has a locking tab. Tug gently on the wires to confirm they are seated and will not pull free during operation.

Step 6: If the igniter tested good, remove and replace the control board

Disconnect all wires from the control board, photographing each connection. Unbolt the board from its mounting location (usually two or three fasteners). Install the replacement board in the same orientation and secure with the original bolts. Reconnect each wire to its original terminal, matching your photograph. Do not skip this step if igniter continuity was confirmed good.

Step 7: Restore power and test the furnace ignition cycle

Switch the breaker back to ON. Set your thermostat to heat mode and raise the setpoint above the current interior temperature. Listen and watch for the igniter to spark and the flame to establish within five to ten seconds. If the furnace lights and holds flame, the repair is complete. If ignition fails again, turn off the thermostat immediately and recheck your wire connections against your photograph.