When and how to replace the glow plug and gaskets of a pellet stove
If your pellet stove is having problems, the cause is often related to two components: the ignition glow plug or the gaskets. How can you tell which one needs replacing? It’s simple:
- Replace the glow plug if: the stove does not start, pellets build up in the burn pot without burning, or the “Failed Ignition” alarm appears.
- Replace the gasket if: you smell smoke in the room, the glass turns black very quickly, or the flame seems to “dance” abnormally (too much air).
Pellet stoves
Pellet stove Cadel series Baggy 7kW
Price range: €1.820,00 through €2.090,00 IVA inclusa
Pellet stovesMaestro M1
Pellet stove MCZ series Mini Air 6 UP-XUP! M1
€3.100,00 IVA inclusaPellet stoves
Cadel pellet stove series Perla 7kW
€1.300,00 IVA inclusaHow can you tell if the pellet stove glow plug is burnt out?
The glow plug (or heating element) is the component that ignites the flame. It doesn’t last forever and is subject to thermal wear.
When to replace the glow plug: 3 clear warning signs
If you notice one of these symptoms, the glow plug should be replaced immediately:
- Cold stove at start-up: the fan runs, pellets are fed, but there is no smoke or initial sparks.
- “Failed Ignition” alarm: the display shows a specific error (often Error Code 12 or similar, depending on the brand).
- Visibly damaged heating element: when inspecting the burn pot area, the glow plug appears blackened, encrusted, or broken.
Quick guide to replacing the glow plug
Time required: 20 minutes | Difficulty: Medium
- Safety: unplug the stove and make sure it is completely cold.
- Access: remove the side (or rear) panels to access the component compartment.
- Locate: follow the wires coming from the glow plug housing tube (behind the burn pot).
- Removal: disconnect the electrical connectors and unscrew the retaining bolt that holds the glow plug in place. Gently pull it out.
- Installation: insert the new glow plug (it must be specific to your model!), tighten the bolt (without overtightening to avoid damage), and reconnect the wires.
- Test: turn on the stove and check that the glow plug becomes incandescent after a few minutes.
When should you replace the pellet stove gasket?
Gaskets, usually made of fiberglass braid or ceramic fiber, ensure the airtight seal of the door. If uncontrolled air enters, combustion loses both efficiency and safety.
The “Paper Test” (or Banknote Test)
The most reliable way to check gasket wear is this simple test:
- With the stove switched off and cold, open the door.
- Place a sheet of paper (or a banknote) between the gasket and the stove frame.
- Close the door.
- Try to pull the paper out.
- If the paper does not move or offers strong resistance: the gasket is still in good condition.
- If the paper slides out easily: the gasket is flattened and must be replaced.
How to replace the door rope gasket
Time required: 30 minutes + drying time | Difficulty: Easy
- Removal: pull out the old gasket from its groove.
- Cleaning (crucial step): use a wire brush or sandpaper to remove all traces of old glue or silicone from the channel. The surface must be clean for the new adhesive to bond properly.
- Application: apply a bead of high-temperature silicone (often included in gasket kits) along the entire perimeter.
- Fitting: insert the new rope gasket without stretching it; lay it gently in place. Cut off the excess with scissors, and place a small piece of tape on the cut end to prevent fraying.
- Drying: close the door and keep it closed for at least 12–24 hours. The pressure of the door helps the gasket take the correct shape while the adhesive cures.
Frequently Asked Questions (FAQ)
You can tell the glow plug is faulty if the stove completes the pellet loading phase but fails to ignite the flame, causing the display to lock with a “Failed Ignition” or “No Ignition” alarm. Visually, you can inspect it: if it appears deformed, broken, or heavily encrusted, it can no longer reach the required incandescent temperature and must be replaced.
The gasket should be replaced when it loses elasticity and no longer guarantees an airtight seal. The main warning signs are:
- Blackened glass: it becomes sooty very quickly (within a few hours).
- Smoke smell: combustion fumes can be detected in the room.
- Paper test: when a sheet of paper is closed in the door, it slides out without resistance (a sign the gasket is flattened).
On average, a pellet stove glow plug has a lifespan of about 2–4 winter seasons, depending on usage intensity. Technically, glow plugs are designed to withstand a specific number of ignition cycles (generally between 2,000 and 3,000). Frequent start-ups shorten their lifespan compared to continuous stove operation.
Cleaning must be done dry and with extreme care. Never use water or chemical products.
- Use an ash vacuum to remove dust around the heating element.
- Gently brush it with a soft-bristle brush or paintbrush to remove surface deposits.
It is also essential to thoroughly clean the housing (the tube) where the glow plug sits, vacuuming any pellet or ash residues that could insulate it and prevent proper contact with the fuel.
