loud banging from rads and pipes when heating comes on

[dedzed]

Helo gents and the odd lady...
I have just spent a nice wedge on a new keston c36 and "brand new-old" cast iron rads (wanted to do it properly).... but i have very loud banging comming from the pipes and one flat panel upright rad in the lounge... now knowing a bit about the mechanics of flow i suggested to the heating engineer that it may be air... so he bled the rads... no luck flushed the system again... still no joy and theres also lots of gurgling and the radiators have to be constantly bled... the engineer is stumped... please some advise..... spent all my money on the installation no more for another engeneer.

 

[seco services]

is the banging constant when heating turn on ?
does it do it on hw only ?
need more info

 

[dedzed]

it only happens when the heating comes on and will eventually go after about twenty minutes and has been known to come back during but for shorter periods... hot water not in use at the time.

 

[dedzed]

p.s it also gurgles and collects air in the upright panel rad.

 

[Goldspoon]

Check your TRV's are on the correct end of the radiators (or are suitable for either end).