How To Fix Gas Fireplace That Won’t Stay Lit & Keeps Going Out

A gas fireplace is a beautiful addition to any home. It looks natural with logs or LED lighting effects, heats your house well, and vents easily. It’s a great way to have that natural fire look without the chimney smoke and ash. With features like remote control operation, they’re convenient to use as well. 

The perfect gas fireplace makes any home feel cozy, but it can be pretty frustrating when it no longer lights. There is often a multitude of reasons on why your gas fireplace might not stay lit. From problems with a faulty gas valve, gas line, gas pressure and more. 

Here are some potential reasons why your gas fireplace may be going out on you and insights on how to get it up and running again. 

gas fireplace being repaired

5 Reasons Why Your Gas Fireplace Won't Stay Lit

1. Pilot Assembly Needs to be Cleaned

When you first turn on the fireplace, you often have to wait a moment for the first flame. You might hear a clicking or the sound of gas being released from the propane tank before the fire springs to life. It all starts from a tiny flame.

That flame is called your pilot light, kept lit by a small stream of gas — it’s essentially your ignition. However, dust can accumulate in your pilot assembly, so it needs to be cleaned out regularly. Sometimes you just might need to reset your gas fireplace pilot light to get it to work or it might be turned off. 

Additionally, your gas fireplace has a thermometer in it, which is known otherwise as a thermocouple. This needs to stay in contact with the pilot flame, consisting of two wires of different metals joined in two places. If the pilot flame dies or dwindles, it will no longer be in contact with the fireplace thermocouple. As a result, the thermocouple shuts the gas off.

When cleaning your pilot light assembly, always make sure the gas is off first. The owner’s manual will tell you where the pilot light is located in the fireplace and whether or not you need to remove it to clean it. 

You’ll want to clean off any soot at the tip of the pilot light, being careful not to bend or dent the assembly while handling it. Use an air compressor to blow inside the pilot light and the thermocouple. When you put it back, your pilot flame should be blue or blue-white in color.

2. Oxypilot Is Blocked With Dust or Soot

The oxypilot is a safety device built into the fireplace so that your carbon monoxide levels are kept safe and regulated. It senses when the oxygen in the room has dropped below an acceptable percentage and, when it does, it turns off the gas valve, extinguishing the pilot light. 

Soot and dust can block the oxypilot, making it automatically lift the flame away from the thermocouple, thus turning off the gas valve.

Like cleaning the pilot light assembly, oxypilot maintenance involves removing soot, dust, and dirt. You’ll want to vacuum around the burner and remove anything that has accumulated there.

If you have logs, remove them from the fireplace and vacuum where they were placed. You should be able to locate the oxypilot, also called the oxygen depletion system, using the owner’s manual. 

Use compressed air to blow away built-up debris and soot. When you’re done cleaning the oxypilot, replace the logs inside the gas fireplace.

gas fireplace

3. Thermopile Is Damaged

Gas fireplaces contain not only the aforementioned thermocouple but also what is known as a thermopile. The latter is actually an interconnected series of thermocouples. 

With each connected thermocouple, the thermopile can conduct more thermoelectricity. The system senses temperature and even radiation in the environment. When the heat hits the thermopile, it generates a voltage that opens the gas valve and allows the fireplace to light. 

A gas fireplace with a thermopile can connect to a thermostat, which you can use to easily control the temperature of the house. If one of the thermocouples in the thermopile is bent, crooked, or otherwise damaged, you’ll have a problem with the fireplace. 

Chances are, this isn’t a problem you’ll be able to fix yourself. Instead, you should call a professional since you shouldn’t take any risks when working with gas. If there’s a problem with the thermopile, an experienced gas fireplace technician will be able to diagnose the issue and explain your options. 

4. Incorrect Gas Pressure

Another common reason why you're gas fireplace won't stay lit is due to an incorrect gas pressure. Unless you're familiar or trained to use a manometer, you will need to call a pro to fix it. This tool is used to check the amount of gas flow through the gas valve, and make necessary adjustments to fix the gas pressure.

5. Moisture In Gas Line

The drip loop is often responsible for trapping any moisture and preventing it from reaching the gas line. There are times when the drip loop won't perform it's function correctly and let in excessive moisture. When this moistures reaches inside the gas line, it can dilute it and create problems. To fix this issue, you just need to replace the drip loop with a new one. 

When cleaning or repairing a gas fireplace, it’s important to find a dedicated local fireplace service for chimney and fireplace systems. Gas appliances can be hazardous if not handled properly, and getting an expert to inspect and possibly repair your fireplace ensures you and your property are kept safe. Even someone for fireplace gas cleaning can be worth it, since it's often deliquate.

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Glenn Wiseman

Glenn Wiseman, Sales Manager of Top Hat Home Comfort Services. Since 1974, Top Hat has been a trusted name in caring for your home. As our services and product offerings have expanded, that same commitment to quality, craftsmanship, and expertise has driven our growth. Using only top-notch suppliers and ensuring top-caliber staff provides you with the Top Hat experience. Our showrooms in Ottawa & Carleton Place have close to 100 fireplaces, wood stoves, and inserts on display, with most operational so you can see before you buy.