Bang noise when turning off radiator

: When a radiator valve is turned off, : there is a loud bang. : This seems to happen on downstairs radiators : and not upstairs. : Is this caused by air in the heating system, : or is there a possible design implication? : Any ideas would be appreciated.Hello Colin,I suppose it can be your ciculation pump with is overpowered , look at that pump for a switch for a lower standard. Sometimes a so called bypass will help in these cases. The bypass is simple to realise , at the most far point from your pump in the 2 pipes of your system If this is not clear to understand let me now by e-mail for an answer.greatingsPeter Tamerus Dutch teacher of plumbing in the Netherlands.

Some radiators wont get hot when system is on, even when air has been removed by bleedingCan anyone suggest what to do?!!.

: Our bedroom radiator in our apt. bangs all night : Our janitor has no solution and we are tired of being waken every night : any possible solutions would be helpful!