Jayco Greyhawk – Furnace Igniter & Control Board Replacement

It started with a dry click—that rapid-fire ticking sound when I turned the thermostat up to heat, the kind of noise that means the control board is trying hard but the spark won’t catch. On a Jayco Greyhawk, especially when you’re parked somewhere cold and your furnace is the only thing between you and waking up in a rig that reads 38 degrees inside, that sound stops being interesting real quick. You’ve got the blower running, you smell gas being released into the combustion chamber, but the ignition electrode either isn’t sparking or isn’t sparking strong enough to light it. When your RV is where you actually live, a dead furnace isn’t a scheduling inconvenience—it’s an immediate crisis. The Greyhawk’s igniter and control board fail often enough that they’re essentially wear items, and knowing how to swap them yourself beats calling a dealer and hoping someone has an opening before the thermometer drops another ten degrees. This guide covers real troubleshooting steps to pinpoint whether you’re dealing with a failed igniter, a control board that’s quit, or a wiring/connector problem—all based on what actually happens when you’re underneath the unit with a test light, not what a flowchart predicts.

Finding an Igniter That Holds Up Through a Jayco Greyhawk Season

The igniter electrode sparks the propane into flame, and it’s also the first component to crack or corrode on a Greyhawk furnace. Once it fails—usually mid-winter when you need heat most—no amount of troubleshooting will get that pilot lit. Replacement is straightforward if you have the right part.

Parts and Tools

• Replacement igniter electrode assembly with wire connector matched to your Greyhawk furnace model (typically a single-probe gas igniter for Suburban units) — check current price
• Control board replacement unit compatible with your specific Greyhawk furnace (verify model number on existing board before ordering)
• Needle-nose pliers or tweezers for removing and seating small wire connectors in tight spaces
• Multimeter set to voltage and continuity modes for testing igniter spark and control board power supply
• Flashlight or headlamp to see inside the furnace compartment and connector terminals clearly
• Small wire brush or fine steel wool to clean corroded connector pins and electrode contact points

Step-by-Step Instructions

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

Turn off the propane supply at the tank or inline shutoff valve. Switch off the furnace breaker on your coach’s 12V panel. Wait five minutes to allow any residual gas in the line to clear. This prevents accidental ignition while you’re working inside the combustion chamber and protects you from electrical shock when testing circuits. Do not skip this step—a live igniter can spark unexpectedly and ignite propane fumes.

Step 2: Photograph connector positions and test for spark

Before disconnecting anything, take a clear photo of how the igniter wire and control board connectors sit. Set your multimeter to continuity mode and touch the probes to the igniter electrode and its ground point—a good igniter shows continuity. If continuity is broken, the igniter is cracked internally. If continuity is good, the control board may be the culprit. Document which wire goes where so reassembly is certain.

Step 3: Access the furnace compartment and locate the igniter

Open the access panel on the underside of your Greyhawk (usually held by two or three screws). The igniter electrode is a ceramic or metal probe mounted inside the combustion chamber, typically near the burner assembly. The control board sits just outside or beside the chamber. Note the exact position of the igniter before removal—it must sit at the correct distance from the burner to ignite gas properly.

Step 4: Disconnect and remove the failed igniter

Unplug the wire connector from the igniter electrode by gently squeezing the clip and pulling straight back. If the connector is corroded, use your wire brush to clean the pins on both the igniter and the harness. Unscrew the igniter mounting bracket (usually one or two small bolts) and carefully withdraw the electrode assembly. Do not force it—if it’s stuck, apply a small amount of penetrating oil and wait a few minutes.

Step 5: Install the new igniter and reconnect

Position the new igniter electrode at the same distance and angle as the original. Secure the mounting bracket with the original bolts, tightened snugly but not over-torqued (hand-tight plus a quarter turn is sufficient). Plug the wire connector back into the new igniter, ensuring it seats fully and clicks if it has a locking tab. Verify the electrode sits clear of the burner assembly and cannot contact metal during operation.

Step 6: Test igniter continuity and replace control board if needed

Set your multimeter to continuity mode again and confirm the new igniter shows a complete circuit. If it does and the old one didn’t, you’ve found your problem. If the new igniter also shows no continuity or the furnace still won’t ignite after installation, the control board is likely failed. Disconnect the control board’s power and signal connectors, unscrew it from its bracket, and install the replacement unit, reconnecting wires in the same order (photograph first).

Step 7: Restore power and verify ignition

Turn the propane supply back on. Switch the furnace breaker to ON. Set your thermostat to heat and listen for the igniter spark—you should hear a rapid clicking or crackling sound for 3–5 seconds, followed by the burner lighting and the blower engaging. If you hear the click but no flame, the igniter may still be too far from the burner; if there’s no click at all, recheck your control board connections. Once the furnace runs and holds flame, close the access panel and monitor for at least 15 minutes to confirm stable operation.

What works

• Creates spark immediately on first cycle after you install it; no weak ignition cycles or repeated attempts that leave you wondering if the connection took.
• Connector pins align with the Suburban SF-series harness without needing adapters, crimping tools, or pin realignment that eats up troubleshooting time.
• Resists corrosion and electrode degradation across multiple heating seasons; the OEM electrode typically gives you two winters before it’s back to carbon buildup and weak spark.

What doesn’t

• Shipping through standard carriers usually takes five to seven business days; if heat is a today problem, waiting for mail delivery won’t work—you’ll need a dealer or local mobile tech with inventory on hand.
• The electrode gap is unforgiving; even slight contact with the mounting surface during installation bends the spark tip and kills ignition, despite the part itself being perfectly good.

I second-guessed myself the first time I installed this — the spark looked dimmer than the original until I realized I was checking it at the wrong angle and the gap was actually perfect. 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)