Top 10 Most Common Fireplace Insert Repair Questions Answered

1. Why won’t my fireplace insert turn on?

If your gas or electric fireplace insert won’t turn on, start with the simple checks. Make sure the power switch is on, the circuit breaker isn’t tripped, and for gas units, that the gas supply valve is open. If you use a remote, replace the batteries and try operating the unit from the control panel instead.

For gas inserts, a faulty thermostat, bad wall switch, or dirty pilot assembly can stop ignition. Electric inserts may fail because of a blown fuse, overheated safety shutoff, or faulty control board.

Call a professional if you smell gas, hear clicking but get no flame after cleaning, or suspect an electrical issue.

2. Why is my fireplace insert not producing enough heat?

When a fireplace insert isn’t heating well, the issue is often airflow, settings, or maintenance, not the burner itself. First, ensure the blower fan is on and set to the correct speed (for units that have fans). Verify that any heat settings or thermostats are turned up high enough and the room’s doors and windows are closed.

A dirty blower, blocked air vents, or clogged filters (on some electric units) reduce heat output. Gas inserts can lose efficiency due to soot on the glass, dirty burners, or incorrect gas pressure.

If you notice weak flame, yellow-tipped flame, or very uneven heating, have a licensed technician check the gas pressure and venting, especially if the unit was recently installed or serviced. 🔥

3. Why does my gas fireplace insert keep shutting off?

A gas fireplace insert that lights but keeps turning off usually has a safety component doing its job. Common culprits include a dirty thermocouple or thermopile, poor draft, or an overheating condition. If the flame is weak or doesn’t fully engulf the thermocouple, it won’t create enough voltage to keep the gas valve open.

Basic steps you can try:

• Clean the pilot area gently with a soft brush or compressed air.
• Check that the glass door is sealed properly (for sealed systems).
• Make sure vents and air inlets are clear of dust or debris.

Call a professional if the problem persists, if the flame looks unstable, or if you smell gas. Frequent shutoffs can indicate venting issues, which are a safety concern.

4. Why is there a gas smell coming from my fireplace insert?

A strong gas odor is always a red flag. Natural gas and propane are treated with an odorant (often smelling like rotten eggs) so leaks are easy to detect. If you smell a strong, persistent gas odor near your fireplace insert:

• Turn the unit off immediately.
• Do not light matches, candles, or use electrical switches nearby.
• Open windows to ventilate.
• Leave the area and call your gas provider or emergency services, then a qualified technician.

A faint gas smell for a few seconds when lighting can be normal, but anything more than that may indicate a loose connection, faulty valve, or leak in the gas line. Never attempt gas-line repairs yourself; only licensed professionals should work on gas piping or valves. ⚠️

5. Why won’t my fireplace insert pilot light stay lit?

If the pilot light won’t stay lit, the most common causes are a dirty or misaligned thermocouple/thermopile, weak pilot flame, or drafts blowing the flame out.

Try this sequence:

1. Turn off gas to the fireplace and let it sit for 5–10 minutes.
2. Remove the glass (if applicable) and clean around the pilot with a soft brush.
3. Relight the pilot following the manufacturer’s instructions, holding the control knob in for the recommended time.

If it still won’t stay lit, the thermocouple/thermopile may be failing or the gas pressure may be off. At that point, schedule service. Persistent pilot issues are not DIY-friendly because they involve safety devices and gas control components.

6. Why is the glass on my fireplace insert turning black?

Blackened glass is usually caused by incomplete combustion, meaning the gas isn’t burning cleanly. This can happen when:

• The air-to-gas ratio is off (improper adjustment).
• Burner ports are clogged.
• Logs or embers are mispositioned, disrupting the flame pattern.
• The unit is burning contaminants like dust, aerosols, or cleaning chemicals.

You can safely clean the glass when the unit is completely cool using a fireplace-specific glass cleaner and a soft cloth. Avoid abrasive cleaners that can scratch and haze the glass.

If soot builds up quickly after cleaning, have a professional adjust the burner and air shutters and verify the log placement matches the manual. Persistent soot can indicate dangerous combustion issues, so don’t ignore it. 🧽

7. Why is my fireplace insert making noise (clicking, humming, or rattling)?

Some noise is normal, especially metal expansion clicks when the unit heats up or cools down. However, persistent rattling, loud humming, or grinding deserves attention.

Common sound sources:

• Blower fan: Dust buildup or worn bearings can cause humming or squealing.
• Loose panels, logs, or screens: These can rattle as the unit vibrates.
• Gas flow: A light whooshing is normal, but loud roaring or whistling isn’t.

You can:

• Tighten loose screws and panels.
• Vacuum dust around the blower intake (if accessible).
• Verify that logs are securely and correctly placed.

If noises are loud, sudden, or accompanied by odd smells or performance changes, stop using the insert and call a technician. A noisy blower or burner can quickly get worse if not serviced.

8. Why is my electric fireplace insert turning on but showing no flame?

For electric fireplace inserts, “flame” is usually a light and motor effect, separate from the heater. If the unit powers on but no flame effect appears, these are likely causes:

• Burned-out bulbs or LED strip in older models.
• Faulty flame motor that spins the reflective component.
• A loose internal connection or failed control board.

Try:

• Resetting the unit by unplugging for 10–15 minutes.
• Checking the flame effect switch/setting—some models let you run heat without flame.
• Ensuring the remote is set correctly and not in a special mode.

If you’re comfortable and the manual allows it, you can sometimes replace bulbs yourself. For anything involving wiring, motors, or circuit boards, it’s best to contact a qualified electric fireplace technician or the manufacturer support. ⚡

9. Why does my fireplace insert smell like burning dust or chemicals?

A mild burning-dust smell is common when you first use the fireplace each season; dust on the heat exchanger and components burns off and usually disappears after a few uses. You can minimize this by vacuuming around the unit and air intakes (when it’s off and cool).

However, strong chemical, plastic, or metallic odors are not normal. These can come from:

• Objects too close to the insert, like plastic decor or cords.
• Paint, adhesives, or finishes curing, especially on new units.
• Overheating electrical components (for electric inserts).

If the smell is strong, new, or accompanied by discoloration, smoke, or unusual noise, turn the unit off and unplug (if electric) or turn off the gas. Let the area air out and have a professional inspect the unit before using it again.

10. When should I repair my fireplace insert vs. replace it?

Deciding between repair and replacement depends on the insert’s age, repair cost, efficiency, and safety.

A general guide:

Repair is usually sensible for younger units with isolated issues like a faulty thermocouple, blower, or control switch. Replacement makes more sense if the insert is 15–20+ years old, parts are hard to find, or you want better efficiency, remote control, and smart features.

Always prioritize safety: if a technician flags serious venting, combustion, or structural problems, replacement or major upgrades may be the only safe path. 🔧

Helpful Tips for Keeping Your Fireplace Insert Running Smoothly

1. Schedule annual professional service for gas inserts to inspect burners, vents, and safety controls; biannual inspections are ideal for heavy use.
2. Clean the glass and visible components regularly with fireplace-safe products to prevent soot buildup and spot issues early.
3. Vacuum around vents and blowers (when off and cool) to keep airflow strong and reduce overheating and noise.
4. Check log and ember placement against the owner’s manual after any cleaning or move; incorrect layout affects flame quality and can cause soot.
5. Test your carbon monoxide (CO) and smoke detectors at least twice a year if you have a gas insert.
6. Keep combustibles clear—maintain proper clearance for furniture, curtains, electronics, and decorations to avoid heat damage and fire risk.