kettling bosch worcester gas fired combi 240

[sandancer]

I am having kettling and tripping out on overheat problems usually when using c/h and d/h/w at the same time. {intermittant fault)

The boiler is now 13 yrs old and the problem first ocurred at the beginning of 2006. I got the B/W engineer out and he renewed the w/w heat exchanger and the thermistor sensor. He also put 1 ltr of sentinel fluid into the system.

This seemed to clear the fault but it reappeared late september of last year when we started using the c/h again.

It may be relevant that I've noticed that when the c/h is off and I run the hot water for a while, the c/h flow pipe ( where it comes out of the boiler)heats up. Or is this normal?.

Can anyone suggest what the problem may be as I don't want to have to fork out another 245 quid on the off chance that they might fix it this time.

Thanks in advance for any advice , which would be greatly appreciated

 

[Bahco]

I don't want to have to fork out another 245 quid

BG do a fixed repair for about £150.

 

[sandancer]

I don't want to have to fork out another 245 quid

BG do a fixed repair for about £150.

Thanks for that, but I had rather hoped that someone could advise me on what the fault might be.

anyone?

 

[petit_pablo]

How long does it run for before it starts playing up and overheating?

Is the pump running correctly, ive replaced sticking pumps on these that caused random O/H.

 

[sandancer]

How long does it run for before it starts playing up and overheating?

Is the pump running correctly, ive replaced sticking pumps on these that caused random O/H.

Thanks for your reply petit pablo.

Being an intermittent fault it sometimes doesn't fail,but when it does, it can happen after a few minutes usually when c/h and d/hw are running at the same time. I presume that I would have to drain the boiler to check the pump, or is it possible to isolate only the pump?
Thanks again.
SD.