banging pipes

[julia34]

Hi

I wonder if you could help me. We recently add radiator into a bathroom and when we start have heating on we noticed a loud banging noise from the pipes. The noise sounds like pipes "twanging" and banging. This banging occur from a start when the CH comes on and when cooling down. The noise we are experiencing upstairs of the house

The Boiler is a Worcester Greenstar 255i/30Si
The CH and hot water do work fine and heat up quickly, (it does not make any noise when the radiators hot).
What we did:
-We insulated around the pipes so they sit tight
-We did bled the radiators
-when we drop the pressure from 2 to 1.5 bar the noise comes but took it longer to get the noise, a ticking noise (I assume expansion) and every now on loud bang from pipes
-sometimes when we turning the radiator valves from ( max to *) we get loud click , that happened upstairs and downstairs of valves
-couple times when we had air comes from a radiator even we did bled the radiators before
Can anyone help? - do I have air in the system? – valves problem?

Thanks everyone in advance.

 

[Nige F]

Hi


-We insulated around the pipes so they sit tight
-
.

the pipes are trapped somewhere - simple as that

 

[julia34]

Hi


-We insulated around the pipes so they sit tight
-
.

the pipes are trapped somewhere - simple as that

what about the air when it comes every now from radiators

 

[julia34]

Hi


-We insulated around the pipes so they sit tight
-
.

the pipes are trapped somewhere - simple as that

what about the air when it comes every now from radiators

and when you said the pipes are trapped what do you mean by that? thank you