Next in our series of the what is of plumbing is what is a boiler gas valve? It's pretty straight forward as the name suggests but it is another important part of the boiler. It also is not cheap to replace. Please note one reason they fail is a build up of dirt or carbon build up. This is normally due to lack of servicing and once the seal has been broken to remove it a new one has to be installed. Unfortunately it is not the cheapest part on your boiler either.
So what is a boiler gas valve and what does it do
The gas supply pipeline runs in to your boiler. Inside the boiler on this supply line a gas valve is fitted. It controls the flow of gas in to the boiler and on to the burner. Every boiler that uses either L.P.G. or natural gas is fitted with one. As you turn the boiler controls up to get more heat the valve opens accordingly letting more gas flow through. If you lower your heating it closes the valve allowing less gas through.
What is a boiler gas valve, the more technical stuff
There are actually 2 gas valves in your boiler. The main one plumbers refer to as the boiler gas valve, the secondary is referred to as the boiler safety valve. If you look at a gas valve, think of two valves in a line. The pilot light is connected via a gas port between the two valves. The valves are operated electromagnetically.
In your pilot light there is a thermocouple or thermopile, when the pilot light is ignited it produces heat. This heat energy is converted to electricity and keeps the safety valve open. When the safety valve is open the main valve or boiler gas valve can draw gas through a much larger pipe to go through the burner trays providing heat. If the pilot light is not lit the safety valve will cut off the supply of gas to the boiler completely i.e. closing the gas boiler valve.
We hope you feel more informed on the subject of what is a boiler gas valve. If you think you have an issue with yours don't try to fix it yourself as this is very dangerous. Call one of the R.G.I. team at plumbers Dublin for free advice and a repair quote on 01-6874853.