Combi seems to be running with no demand...

[charliegolf]

Mine's a Nov 2011 model

Edit: I didn't really understand the last few posts! I picked up leaving it to the next service- ok to do that? Everything works at present. Thanks.

 

[Agile]

Well you have to decide if it is bothering you enough to want it sorted out quickly or just wait until the next annual service!

My quick calc shows it might use £10 of electricity in a year running constantly.

Tony

 

[McCombi]

Depends when you want it fixed really.

If it is a faulty pump (sounds the case by what you've written previously) a service isn't going to cure it. The pump will need to replaced by a registered gas man.

 

[FiremanT]

As per mcCombI, don't wait for the service guy time turn up before telling him. Dont take Tonys advice too seriously. Ever. The service guy may need to allocate more time.
A "service" is a predetermined range of operations. You are talking about a "repair" which may or may not be manageable on the service visit.

He may have to pack his oscilloscope and listening stick

 

[aptsys]

I think you're misunderstanding Tony, but the points still stand.

 

[charliegolf]

UPDATE: after a week of visitors taking my attention, I had a light bulb moment, and switched the boiler off! On switch-on, the rumble is gone, and the boiler fires up on hot water demand as it should. I'll keep an eye on it. Thanks for the responses.

CG