Combi boiler hit and miss with heating

[junglistmatty]

Our combi boiler is not firing up when we turn the heating on, but for hot water its running fine and fires up as soon as a hot tap is opened.

It's one of these:

Worcester junior combi boiler - either a 24i or a 28i, I can't see anywhere on the boiler where the model number would be.


It fired up the other day after resetting the boiler, but since then can't get it to fire up at all. Our heating controller is made by Honeywell.... is it possible it's the controller?


Any ideas to troubleshoot?

 

[Agile]

Well........ where do you want me to start?

Its often external controls. They are easily checked by someone with a little electronics knowledge.

Then the boiler, there could be faults preventing the heating from working.

I have also seen a PCB causing that problem.

Tony

 

[dcawkwell]

Fault in timer or wall thermostat.

Failing that.

Remove one of the leads to the flow sensor at the back(very awkward
what idiot designed it like this).
boiler should stop firing on hot water.
boiler should then fire up and do central heating.

Faulty flow microswitch / or flow switch.

 

[junglistmatty]

I got a plumber out to fix this....

Cost me £210 for them to replace a faulty controller!!!!!!..... I'm in the wrong industry