Can someone take a listen to this and advise what might be the problem please? It keeps going onto overheat and the radiators don't get hot:

https://youtu.be/XKH-jZTGbVc

Tony Lee, December 2015

Called British Gas out again. Same guy turned up this morning ... the pump was faulty! You couldn't make it up!

Tony Lee, December 2015

The speed of the pump is adjustable I believe - you might try turning the speed up and or the water temperature down - the overheat cut-out operates because the water gets too hot.

And in the evenings you might be placing a higher demand on the boiler - running baths - turning the room thermostat up - your noises are probably normal running noises - your issue is the over heat situation.

I am not a boiler engineer..., December 2015

We've got British Gas insurance and called out an engineer numerous times, but they never seem to find anything obviously wrong. As is typical, when the engineer turns up, the boiler starts behaving, but it seems to be worse in the evenings. It's lucky we're having a mild winter so far.

Tony Lee, December 2015

I heard various noises but have no opinion because I'm unaware of what it used to sound like....

There's a pump to pump the water around the radiators - if the pump stops working the water in the boiler risks boiling and becomes too hot for safety - the overheat cut-out operates.

And if the pump's not pushing the water around the system the radiators will not heat up.

This may be your problem - I am not qualified to make this amateur diagnosis.

Call in a specialist as soon as you're able.

Good Luck..., December 2015