Combi Boiler - Intermittent Humming/Banging

[TimH]

Hi

We recently had Main 24he Combi boiler installed. After the heating has been on for a bit we suddenly get a humming which can progress into a banging. This can be cured sometimes by turning some of the TRV's off or, otherwise by simply turning the boiler off for 10 mins or so. There is also some air rushing in the system too.

I don't know if both are related but would be grateful for some sound (excuse the pun) advice.

Thanks

Tim

 

[fanboy]

Has the boiler been adapted onto an old system, i.e old pipework?

 

[TimH]

Yes, it has. Used to be gravity fed system.

 

[picasso]

do you have thermostatic radiator valves fitted and if so how old are they?

 

[TimH]

Yes. TRV's installed on all but one radiator.

 

[TimH]

TRV's installed with boiler 10 mths ago.

 

[fanboy]

It sounds like you have poor circulation in the system. This can be caused by various problems, sludge in system, lazy pump etc.

Personally i would check the pumps operation and add a bottle of sentinel x400 sludge remover.

 

[TimH]

The system was flushed when it was installed. I will try again. Where do I fill from? Sealed system

 

[TimH]

i.e. When the boiler was installed on the old system. When the radiators are bled the water has a slight whitish tinge to it.