Flushing central heating system

[sabres]

I am replacing all radiators and putting in a new boiler. As the system will be entirely drained is it still neccessary to power flush it. If so, do I do it before the new installation or after?

 

[oilman]

You need to clean the system so there is no flux residue if you use solder joints, to remove copper shards where you have cut pipes and to shift any other foreign bits. You don't necessarily have to powerflush, but you may not have the guarantee benefits from the boiler manufacturer if you don't.

You say you are installing a new boiler? Is it gas or oil or solid fuel? Are you doing it or is an installer doing it for you? If you are doing it, do you have approval from the building control dept of your local authority? If you don't, you might be in the doo-doo when you come to selling the house. Not to mention the now criminal offences, since April 2002.