Main combo heating not coming on correctly

[trevorbayliss]

My main combi is 3 yrs old.

The hot water is working fine.

The central heating is working as well, but it is not coming on correctly. So i think this is a fault with the communication between the thermostat or communication inside the boiler

This is what happens:

I turn the dial on the stat (wired and a basic dial operation, 3 yrs old). The green light on the heating indicator on the boiler comes on.

The ignition will not fire, however.

So if i turn the boiler to zero it will all turn off. I then turn it back on again and the ignition will fire up and the heating comes on.

Any ideas on this fault ?

 

[Agile]

What do the boiler lights show?

 

[trevorbayliss]

The light for the heating shows green which indicates the thermostat is talking to the boiler, but the ignite indicator does not come on (yellow burning colour).

If i switch the boiler off and on, the green heating comes on and then the ignition light fires on with the ignition.

No fault codes.

Just spoke to main technical and they say sounds a bit strange. But try the thermostat first. This was my first inkling as well. So i will try replacing the stat on monday and see if this resolves this issue.

They have not has this issue before. They would try bypass the stat on the boiler electrics to test is all is ok with the boiler first, but i can't do this unless i get an engineer. So cheapest option is to try a new stat first and maybe take it back if this isn't the fault.