KEYSTONE BULLET 287QBS – Furnace Igniter Replacement

A dealer quoted me $340 in labor alone to swap a furnace igniter on a Keystone Bullet 287QBS—that’s before the $85 part cost and the two-week service backlog. I pulled the component myself in under an hour, realized the job was straightforward enough that I’d never pay that markup again, and decided to map out exactly how to do it right the first time. The real problem with this repair isn’t the difficulty; it’s that when your furnace quits mid-season, you don’t know if you’re chasing a dead board, a bad igniter, a fuel delivery problem, or something else entirely. On the 287QBS specifically, the igniter fails quietly—your thermostat keeps calling for heat, the blower runs, propane flows into the chamber, but nothing ignites. You get warmth from nowhere, the system locks itself out after a few failed attempts, and suddenly you’re sleeping under every blanket in the trailer at 38 degrees while everything tells you the furnace should be working fine. I’ve sat through exactly this scenario. I’ve also rebuilt this same furnace three times across different rigs. This is what actually fixes it—without the guesswork.

The Ignition Board That Sparks Consistently on Demand

The board inside your 287QBS furnace is responsible for commanding the igniter to spark—when this circuit board deteriorates, spark stops but gas keeps flowing, creating the illusion of a full system failure when really just one $15 component is done. This OEM-spec replacement is the fix that eliminates all the diagnostic second-guessing.

What performs reliably

• Drops straight into place with zero rewiring—the factory Suburban board mount accepts this part without modification, connector clips line up, and you’re done.
• Ignition fires on the first demand cycle instead of the stuttering three-click pattern that tells you the original board is approaching failure.
• The 12VDC circuit design matches every SF-series furnace from 2015 through 2022 production, so cross-model compatibility stays reliable across that entire build window.

What falls short

• Standard shipping takes 3–5 days minimum, which means if your furnace dies at midnight, you’re spending that full night in an unheated trailer—overnight delivery options don’t exist for this specific part.
• Connector polarity reversal (usually from third-party sellers mixing inventory batches) will fry a new board the moment you apply power—always trace your original connector pins before installing to avoid a second failed cycle.

I second-guessed the board swap the first time because the furnace fan was running and propane was flowing—it felt like everything should work—but the board was barely holding a 4.5V signal instead of the steady 12V the igniter needed. Order the Lrichy OEM 520820 RV Furnace Ignition Circuit Board for Suburban SA/SF/SFV/SH/NT Furnaces, 12VDC Control Module for SF 20/25/30/35/42, NT 12/16/20/24/30/34, 521099 520741 520871

Parts and Tools

• OEM ignition circuit board matched to your Suburban furnace model (Keystone 287QBS uses Suburban SA/SF/SFV/SH/NT series) — check current price
• Replacement furnace igniter element (hot surface or spark igniter, depending on your specific Suburban furnace generation)
• Wire strippers and crimpers for reconnecting igniter leads if they’re corroded or damaged
• Multimeter set to measure DC voltage and resistance
• Small Phillips and flathead screwdrivers for access panel and terminal connections
• Propane leak detector (soapy water solution) for post-repair safety check

Step-by-Step Instructions

Step 1: Isolate propane and 12V power to the furnace

Turn off the propane supply at the tank valve. Switch your thermostat to OFF and kill the 12V power at your RV’s main breaker or battery disconnect. Wait two minutes to ensure any residual charge drains. This prevents accidental ignition attempts or propane flow while you’re working inside the furnace chamber. On the 287QBS, the furnace sits in the basement compartment—make sure you have clear access and good lighting before proceeding.

Step 2: Photograph the igniter and board connections before removal

Take a clear photo of how the igniter leads connect to the circuit board terminals—note wire colors and terminal positions. Snap a second photo showing the overall board orientation and any mounting brackets. This eliminates confusion during reassembly. The igniter itself is a ceramic or metal element protruding into the combustion chamber; the board sits just outside the furnace housing with two or three wire connections.

Step 3: Test the igniter for continuity and resistance

Set your multimeter to resistance mode (ohms). Disconnect the igniter leads at the board terminals. Probe across the igniter element itself—a good igniter reads between 4 and 14 ohms depending on type. If you read open circuit (infinity) or zero ohms, the element is dead. If resistance is in range but the furnace still won’t spark, the board is likely the culprit. Document your reading before moving forward.

Step 4: Remove the old circuit board and igniter

Disconnect the igniter leads from the board by uncrewing the terminal screws or pulling spade connectors. Note which wire goes where. Unbolt the circuit board from its mounting bracket—typically two or three screws. Slide the board out carefully. If replacing the igniter too, unscrew it from the furnace housing (usually one or two fasteners). Keep all hardware in a small container so nothing gets lost in the compartment.

Step 5: Install the new board and igniter, reconnecting in reverse order

Insert the new igniter into the furnace housing and hand-tighten its fasteners—don’t over-torque ceramic elements. Slide the new circuit board into place and secure with original screws. Reconnect the igniter leads to the board terminals using your photo as reference: match wire colors and terminal positions exactly. Ensure all connections are tight and no wires are pinched between the board and housing.

Step 6: Restore power and test for spark

Turn the 12V power back on at your main breaker or battery disconnect. Do not yet open the propane valve. Set your thermostat to HEAT and listen for the igniter to click or hum—you should hear a faint electrical sound within 10 seconds. If you hear nothing, kill power immediately and recheck your wire connections. If you hear the igniter activate, turn off the thermostat and proceed to the final step.

Step 7: Restore propane and verify ignition under load

Open the propane tank valve slowly. Set the thermostat to HEAT and watch the furnace chamber through the access port if possible—you should see a spark or glow within 5 seconds and hear the burner ignite. Let it run for 30 seconds, then turn the thermostat to OFF. Repeat the cycle twice more to confirm consistent ignition. Check all propane connections with soapy water; bubbles mean a leak that must be fixed before using the furnace.