Forest River Cedar Creek – Furnace Igniter & Control Board Replacement

Hey there, I’m Drew Callahan, and as someone who has clocked over 80,000 miles across North America in three different rigs, I’ve encountered my fair share of furnace issues in Cedar Creek units. If your furnace is clicking but not igniting, or worse, shutting down in the middle of a frigid night, you’re likely facing a failing igniter or control board. This isn’t just an inconvenience; it’s a genuine concern. Forest River often cuts corners with components that are merely adequate for passing inspections, which can lead to problems down the road. I’ve seen this firsthand: the igniter and control board in Cedar Creek models tend to misfire after just four or five seasons of temperature fluctuations and road vibrations. The stakes are high—not only could you be left without heat, but a malfunctioning igniter can cause raw propane to build up in your ductwork, creating a serious hazard. In this post, I’ll guide you through the diagnostic and repair process that I’ve used in my own rigs to tackle this exact problem.

The Full Replacement That Finally Stopped the Mid-Winter Shutdown Cycle

When you’re dealing with intermittent furnace failures in a Cedar Creek, I can tell you from experience that replacing parts one by one is a recipe for frustration. The best solution I’ve found is to replace the entire Suburban/Atwood furnace assembly. This way, you can put an end to the diagnostic roulette that plagues you during those freezing nights.

Parts and Tools

• Suburban/Atwood RV furnace replacement unit matched to your Cedar Creek model’s BTU rating and mounting configuration — check current price
• Propane line wrench or adjustable wrench sized to fit your furnace inlet connections (typically 1/2 inch or 5/8 inch)
• Teflon tape for sealing propane line threads
• Furnace mounting bolts or hardware kit specific to your Cedar Creek model year
• Electrical connector kit or replacement connectors if factory connectors are corroded or damaged
• Ductwork sealant or aluminum foil tape for resealing any ducting disconnected during removal

Step-by-Step Instructions

Step 1: Isolate propane and electrical power

Turn off the propane supply at the main tank valve. Switch off the furnace breaker on your 12V DC panel and disconnect the negative battery terminal. Wait five minutes to ensure all residual power drains. This prevents accidental ignition attempts while you work and eliminates shock hazard. Take a photo of your current wiring connections before disconnecting anything—label each wire with tape if your connectors aren’t color-coded.

Step 2: Access and document the furnace location

Locate your furnace, typically mounted in a basement compartment or under-floor cavity in Cedar Creek models. Remove the access panel by unbolting or unlatching it. Photograph the entire furnace assembly from multiple angles, showing how ducting, propane lines, and electrical connectors attach. This reference prevents confusion during reinstallation. Note the orientation of the furnace and any brackets or spacers supporting it.

Step 3: Disconnect propane and ductwork

Using your wrench, carefully disconnect the propane inlet line at the furnace fitting. Have a small container ready to catch any residual propane liquid. Disconnect the hot air outlet duct and return air inlet duct by loosening hose clamps or removing fasteners. Slide ducts away gently. If ducting is sealed with caulk, use a utility knife to cut it free. Do not force ducts; they may tear.

Step 4: Remove electrical connectors and mounting hardware

Disconnect the igniter and control board electrical harnesses from the old furnace. These typically plug into the board with simple push connectors. Unbolt the furnace from its mounting brackets using your socket set. In Cedar Creek units, expect four to six bolts. Keep all hardware in a labeled container. Carefully slide the old furnace out of the compartment, supporting its weight to avoid dropping it or damaging surrounding cabinetry.

Step 5: Install the replacement furnace and reconnect ducting

Position the new furnace into the compartment, aligning it with the original mounting points. Install and hand-tighten all mounting bolts first, then torque them snugly—do not over-tighten, as furnace housings can crack. Reconnect the hot air outlet and return air inlet ducts, securing them with hose clamps. Ensure ducts are fully seated and clamps are tight enough that they don’t slip under vibration.

Step 6: Reconnect propane and seal the line

Wrap the propane inlet fitting threads with three to four layers of Teflon tape, wrapping clockwise. Hand-tighten the propane line to the furnace inlet, then use your wrench to snug it an additional quarter-turn. Do not over-tighten; propane fittings are brass and strip easily. Once connected, apply soapy water to the joint and watch for bubbles while the propane is on—any bubbles indicate a leak requiring retightening.

Step 7: Reconnect electrical and test ignition

Plug the igniter and control board electrical harnesses into the new furnace, matching connectors to their original positions. Reconnect the battery negative terminal and switch the furnace breaker back on. Turn the propane supply on at the tank. Set your thermostat to heat and listen for the igniter clicking and the furnace firing within 10–15 seconds. If it ignites cleanly and runs for a full cycle without shutting down, the replacement is successful.

Step 8: Seal the access panel and verify operation

Reinstall the furnace access panel and secure it with bolts or latches. Run the furnace for at least 20 minutes on a heating cycle, checking that warm air flows steadily from vents and the furnace cycles off when the thermostat is satisfied. Feel the propane line connection for any warmth or moisture, which would indicate a leak. If everything runs smoothly and no propane smell is present, the job is complete.

What Works

• Drop-in compatibility with Cedar Creek’s factory mounting—no need to worry about custom brackets or unexpected rewiring midway through the job.
• With a new igniter, control board, and blower all included as a matched set, you can forget about the guessing game of whether an older igniter will work with an old board.
• Suburban/Atwood furnaces are more durable than the OEM Cedar Creek units. I’ve seen these models run reliably for over 8 years on the road without any repeat failures.

What Doesn’t Work

• This is a more involved job than simply swapping out the control board; you’re pulling the entire unit, which means disconnecting vents and setting aside a solid afternoon for work in cramped spaces.
• If your current furnace is still technically operational, this isn’t the most budget-friendly option. Think of it as an insurance policy rather than a quick fix.

There was a time when I almost convinced myself to get through one more winter by just swapping out electrodes and resetting boards. But then I realized I was spending $80 to $120 every couple of months on parts that only masked a bigger issue. Instead, I decided to invest in a Suburban/Atwood RV furnace replacement unit so I could actually sleep warm at night.

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