Banging central heating

[stuartinlancashire]

For a couple of weeks now my girlfreinds central heating has been making a banging noise.

I've bled all the radiators but this does not seem to have cured the problem!

The banging occurs even when the heating is off and it's just the hot water thats on. Any suggestions would be appreciated.

Thanks

 

[jumbo55]

always tell us what boiler it is stuart, and whether its a combi or not, at a guess, it could be the pump, but would need to know more about the system, has it always been like that, did it start when she turned her heating on, as much info as poss, that gives the engineers on the site a chance to help you properly. when you bled the rads did you get water out of all of them?

 

[stuartinlancashire]

I'm not at her house at the mo so sorry for the sketchy details, all that I can say is that it's not a combi, and it is a baxi but dunno what model.

I'm going to try bleeding the rads again this weekend but I'll let more water flow out this time to see if it makes a difference. I did get a good jet of water from each rad and there did not appear to be any trapped air.

 

[clf-gas]

Check small header tank in loft or cupboard, does it have water in?.

 

[gas4you]

If you check what craig said and it is ok I would check the pump. Could be stuck or knackered. Put a towel under it and undo large screw in center, then put flat bladed screwdriver in and see if you can turn it.