If you smell gas, do this first
Leave the building right away and get everyone out. Don't flip light switches, unplug anything, use a phone or light any flame inside. Once you're outside, call the gas utility or 911. Don't try to relight the fireplace or look for the leak yourself.
When a gas fireplace won't light
A gas fireplace has a short chain of parts that all have to work in order. Gas has to reach the unit, the igniter has to make a spark, and the pilot flame has to heat a safety sensor that tells the valve it's safe to send gas to the burner. If one link fails, the fireplace stays dark. It can also light and then shut off a few seconds later. That shutoff is a built-in safety feature, but it doesn't tell you which part has failed.
Common signs
What homeowners usually notice
- You hear clicking, but the pilot never lights
- No clicking or spark at all when you press the igniter or use the remote
- The pilot lights while you hold the knob in, then goes out when you let go
- The pilot stays lit, but the main burner won't come on
- The pilot is small, weak, yellow or flickering instead of a steady blue flame
- The fireplace lit last season but won't start after sitting unused
- The remote or wall switch stopped doing anything
Possible causes
The symptom points toward a cause, but it doesn't confirm one. A technician confirms the cause by testing the parts with the unit opened up. These are the usual possibilities.
Symptoms and what might be behind them
01Clicking but no pilot flame
- What you may notice
- The igniter sparks, but the pilot doesn't catch.
- How it’s confirmed
- The technician checks whether gas is reaching the pilot, looks for a dirty or partly blocked pilot opening, and checks the position and gap of the igniter.
02No spark at all
- What you may notice
- Silence when you press the button or use the remote.
- How it’s confirmed
- The igniter, its wire, the batteries in the remote and receiver, the wall switch and the electronic ignition module are tested.
03Pilot goes out when you release the knob
- What you may notice
- The flame lights while you hold the knob, then dies within seconds of letting go.
- How it’s confirmed
- The thermocouple or thermopile is tested to see whether it produces enough signal, and the technician checks whether the pilot flame is actually reaching it.
04Pilot stays lit, burner won't come on
- What you may notice
- A steady pilot, but no flames on the logs when you switch it on.
- How it’s confirmed
- The thermopile output, the switch and its wiring, the remote receiver and the gas control valve are checked.
05Weak or lazy pilot flame
- What you may notice
- The flame is small, yellow or flickering, or it barely touches the sensor.
- How it’s confirmed
- The technician inspects the pilot assembly for dirt, soot or debris and checks the gas pressure at the unit.
06Shuts off after running a few minutes
- What you may notice
- The fire starts normally but goes out on its own.
- How it’s confirmed
- Venting is inspected for blockage, and any venting safety switch on the unit is tested along with the pilot sensor.
Simple checks that are safe to make
Only make these checks if there is no gas smell. Replace the batteries in the remote and in the receiver, if your unit has one. Make sure the wall switch is on. Check that the gas valve for the fireplace is in the open position. Then follow the lighting instructions printed on the label that came with your unit, including how long to wait between attempts. If the fireplace still won't light after that, stop and have it looked at.
How urgent is it?
A fireplace that simply won't light is usually not an emergency. The safety system is shutting off the gas, and that is what it's designed to do. Some signs mean you should stop using it completely until it has been inspected.
- Any smell of gas, even faint. Leave the building and call the gas utility or 911 from outside.
- A loud whoosh or small boom when the burner finally lights (delayed ignition)
- Soot on the glass, logs or wall above the fireplace
- Cracked or loose front glass
- Flames that look tall, ragged or orange, or that reach out of the firebox
- Scorching, melting or unusual heat around the unit
What normally fixes it
The fix depends on what testing turns up. Common repairs include cleaning the pilot assembly and its gas opening, replacing a worn thermocouple or thermopile, replacing an igniter or ignition module, repairing switch or receiver wiring, and clearing blocked venting. Replacing the gas control valve is less common. Our gas fireplace repair service covers both finding the cause and making the repair, and we work on all major brands.
Many lighting problems start with dust, spider webs or debris that builds up in the pilot area between uses. Regular gas fireplace service and maintenance cleans and checks those parts before they fail.
What not to do
- Don't keep pressing the igniter over and over. Gas can build up in the firebox between tries.
- Don't hold a match or lighter to the burner unless your unit's lighting instructions specifically call for it.
- Don't bypass, jumper or remove the thermocouple, thermopile or any safety switch.
- Don't take apart the gas valve or loosen gas fittings.
- Don't run the fireplace with the glass front removed or cracked.
If you're still deciding what kind of fireplace suits your home, our guide comparing gas and wood-burning fireplaces explains how the two differ in everyday use and upkeep.
Related work covered on this page
- Gas Fireplace Service & Maintenance
