pilot will not light on thorn M44/54B gas boiler

Tony, September 2015

"unable to light pilot"

When lighting the pilot the following has to happen

Gas valve button pushed IN

Hiss of gas is AUDIBLE

Spark ignitor is depressed (several times if necessary)

Pilot lights

After approx 30 seconds the thermocouple has been warmed up sufficiently by the pilot light for you to turn the gas valve button to main burner

Pilot light should remain lit & not click off

"unable to light pilot"

Does that mean

No pilot flame at all when holding gas valve button & pushing the ignitor?

Or no hiss of gas when pushing button

Or no sparking

Or pilot lights but wont stay on when turning gas valve button

Etc etc etc

Need more information in order to be able to accurately diagnose fault

At the moment with the information you have provided it could be one of a dozen causes

In the absence of standing in front of the boiler I am relying on you to provide the necessary information in order to accurately diagnose the fault

The questions I have asked do not require any specialist test equipment

You just have to LOOK LISTEN & SMELL if necessary

Q, September 2015

First the call for heat
then the fan
then the pressure switch
then the pilot gas valve and the spark to light it.

Can you hear the fan? - can you hear or see the spark?

Good Luck..., September 2015