Pilot light on gas boiler

Mr Pounder Esquire formulated the question :

Is it not lighting, or not staying in once lit? Can it be made to light with a match? and stay lit?

My old boiler went this way and I found that a black deposit was partially blocking the pilot jet. They are fiddly to clean and great care is needed to make sure you dont chip the ceramic jet as it then lets too much gas through and burns yellow and you have to buy a new jet.

If you look at the body of the gas valve, you may find an adjusting screw for the pilot light.

If the flame is too small, it blows out/doesn't heat the thermocouple adequately.

If it's too big, it burns the thermocouple out too quickly.

So, it probably needs adjusting to make it bigger.

He needs to be told that pressing the button is the only way to get gas to the pilot. Has he been using matches - if so the pilot jet could have debris in it.

He managed to light it yesterday, then it went out again. Seems the pilot light is behind a glass shield and is very difficult to get to. The sparker did not ignite the pilot light. He said that he could hear the gas.

That sounds reasonable. Sent on. Thanks.

No, he has not used matches. The pilot light is behind a glass shield and is very difficult to get to.

"Mr Pounder Esquire" snipped-for-privacy@RationalThought.com wrote in news:putfdk $hs4$ snipped-for-privacy@dont-email.me:

Perhaps the spark gap has become large and the lead is tracking to earth. Maybe dirt has diverted the gas from the spark area.

These open flued boilers really must be serviced annually. They are easily capable of generating carbon monoxide back into the house if not running properly.

Soot due to incomplete combustion drops back into the burners (and often the pilot jet too). This leads to even less efficient burning, more soot production, and the boiler can quickly 'run away' with soot production, pouring out carbon monoxide.

You certainly want a CO detector in that room, and in your bedroom.

Its sounds like a partially blocked pilot jet - hard to light and not quite enough flame to hold in the solenoid reliably.

Seems that The Man is to visit him and sort it it out.

I?d check the flame sensor was clean and in the flame. One of our old boilers was prone to this, the sensor was a brass like tube which sat in the flame. It got soot on it and needed to be right in the flame for optimal working.

Of course, there are other types of sensor, so this may not apply.