Easy Fix: Gas Fireplace Won’t Stay Lit

When handling appliances that use gas or electricity in your homes such as gas fireplace, furnaces and heaters you have to be extra careful. They could be dangerous if not properly handled. Call an expert when you feel you are not confident to handle them.

There are various causes that can be the reason why your gas fireplace won’t stay lit. When starting your troubleshooting process check if the pilot lighting is functioning properly. In most cases, the pilot is usually the reason why your gas fireplace won’t stay lit. Here are some reasons that may be contributing to your pilot lighting problem:


This is a small piece of metal that acts a safety device. It triggers the gas flow when it gets heat up. It supplies pilot light with gas from the gas valve. To check if your thermocouple is faulty follow the following steps:

  • 1. You need a multi-meter and set it to Ohms (the two leads of the meter should have a zero reading when in contact)
  • 2. Remove the thermocouple from the system (use the manufacture’s guide)
  • 3. Ignite a flame and place the tip of the thermocouple into contact with the flame
  • 4. Ensure that the tip is very hot. Measure the hot thermocouple tip and the rare side that makes contact with the gas valve
  • 5. The reading on your multimeter should be equal or higher than 25 millivolts. This is the standard voltage needed for the pilot flame to stay on. In case it is lower than that then you need to replace it

The Drip Loop

Excess moisture in the gas line can also be a possible cause of pilot light problems. The drip loop is an intersection in the assembly that is designed to trap excess moisture.

Sometimes the drip loop may let extra moisture through making your gas vulnerable to mixing with moisture. This dilutes the strength of the gas causing problems you are experiencing. A worn out drip loop can be replaced.

Clogged Burner

Sometimes gas fireplace won’t stay lit because it is not receiving sufficient gas to keep the flame going. The color of the flame can be an indicator of the gas flow. Because this is a real flame, will not effect like that of electric fireplaces.

The burner is placed below the thermocouple and pilot. It contains tiny holes that pass through the gas. When your gas fireplace won’t stay lit is may be because these holes are clogged with dirt. You can clean the holes using an air compressor or water. However, when you use water to ensure that you dry it thoroughly.

Pilot Flame Color


The flame produced should be hot enough and engulf all the triggers. The ideal flame color is supposed to be bright blue. When you notice a yellow flame it is not a good indicator because it means that the sensor is not getting enough heat energy to trigger them.

The color of the flame is the indicator whether it I bad or good. You can replace the pilot assembly or clean it out with a wire brush. Sometimes the flame is poor due to impurities in the assembly.

The Gas Valve


Via mygasfireplacerepair.com

The gas valve is usually the last option when troubleshooting why your gas fireplace won’t stay lit. It is a rare case to get a malfunctioning gas valve but we cannot completely rule out its possibility.

We recommend that you use experts when you detect that the gas valve is the problem. The diagnosis of the gas valve can be done visually.

Wall Switch Malfunction

Faulty wall switch may be the cause why your gas fireplace won’t stay lit. This is a common problem for most gas fireplaces.

Thermocouple and thermopile are directly connected to the wall switch. When your wall switch is flipped on it transmits current that triggers the flame.

Over time your voltage at the wall switch reduces which translates to less voltage being transmitted to trigger the flame. This may be due to corroded contacts, dirt covered contacts or broken connection.

Open the wall switch ad expose the wires. You will find two wires. Disconnect the wires from the switch and bring the two wires into contact. Observe if the fireplace comes on. If it does then the switch is the problem and you may be required to replace it.

When your fireplace does not go on then you have to “jump the valve”. Go to the valve and spot the contacts that are labeled TH and TP/TH. Take a wire and connect TH and TP/TH directly.

By doing this you are bypassing all the safety switches and fuse to see if the problem is in between the valve and the wall switch. If your fireplace goes on then the problem lies within the current path.


Troubleshooting is the hectic part of repairing your gas fireplace complications. The current is usually below 1 volt and you don’t have to worry about being electrocuted.

The above problems diagnosis is the common causes your gas fireplace won’t stay lit for long. In case you reach a dead end then you will have to call an expert and get their opinion on it.

  • Learn more about fire pits and fireplace for your residential home design


I am Vera Watson. Drawing The House is a dream that was conceived when I saw a niche in consumer guide on almost everything in our homes. My main aim is to help you save money by testing the products you need and recommending you the best of them all. I believe in the family as an institution and the first way to make a family happy is providing the best for them.

Click Here to Leave a Comment Below 2 comments