How to Fix a Gas Fire that Keeps Going Out
There are two gas fires in our house, one in the living room, the other in the kitchen. The latter keeps going out after about half an hour, even when the dial shows it as on. Though I don't worry too much about carbon monoxide poisoning, there must be some safety device to shut off the gas valve.
After doing some research, I now have basic knowledge about gas fires and fixed my gas fire fault. Here's an easy way to do it:
- Blow through a drinking straw over pilot/thermocouple area to clean them out. (This saved us at least £30.)
Different makes and models have different safety devices. Some have only a thermocouple and some have an oxypilot that is an atmospheric vitiation sensing device. Learn more about these below and how to fix yours so that your gas fire won't keep going out.
When you first start the fire, keep it on the pilot light for a couple of seconds, and the fire should "kick on" when you turn the dial from the pilot light to the on position. Sometimes you need to hold the pilot light on for longer to ignite the main fire.
- When the pilot is lit, there should be two flames — one over the burner and the other (smaller one) touching the thermocouple.
- If you get dust in the pilot assembly and the pilot needs to be cleaned out, it produce a "lazy" flame, and that will be disturbed by the draught of the main burners. The flame lifts away from the thermocouple and cause the temperature on the tip of the thermocouple drops, this, in turn, makes the gas valve shut off.
- The fire produced on pilot should be sky blue in the middle and dark blue in the outer flame, rather than a flame tinged with yellow. It should be directed at heating the tip of the thermocouple.
- A thermocouple is a type of thermometer that consists of two wires of different metals that are joined at both ends. One junction is at the temperature to be measured while the other is held at a fixed lower temperature.
- The current generated in the circuit is proportional to the temperature difference. The thermocouple works by this difference, thus it allows gas from the gas valve to the gas fire main burners only when the tip of the thermocouple stays in constant contact with the pilot flame.
An oxypilot is an atmospheric sensing device in place to put out the gas fire if there is insufficient oxygen in the room. It is designed as a safety device to protect you from carbon monoxide poisoning if the air in a room becomes vitiated.
Basically, if the oxygen percentage in a room drops, the flame shape is altered by its incomplete combustion and the heat is removed from the thermocouple shutting off the gas valve. If the oxypilot becomes blocked with dust or soot the flame lifts away from the thermocouple or flame sensing electrode, this will make the fire cut out, or pilot not light.
- Between the pilot supply pipe and the pilot burner, there's a brass tail or connector. There'll be a small hole on one side —make sure there's no dust blocking this, and clean if needed.
- Then, place a bit of tubing or a drinking straw over each pilot hole, and blow down it to clean it out.
CORGI Registered Gas Installer
Even if you have knowledge of gas fire, you still need a CORGI registered gas installer to work on gas appliances when you have to break or disconnect any gas supplies or fittings or try to change parts.
- Gas appliances should be serviced every 12 months.
- Hiring a CORGI engineer to service the fire involves removing the gas fire and checking the chimney with a smoke pellet. He should also clean the fire and clean and/or replace the pilot assembly or take the burner tray out to get at the thermocouple to change it. This may cost you around £30 - £50 or more.