central heating pipework Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[geoff1057]

am i right in saying, on a double pipe heating system, the main feed and return pipes are 22mm, and teeing off to radiators, feed and return pipes are 15mm. ..........and if i added another rad i tee into the 22mm feed and 22mm return.....with 15mm speedfit , would that be ok ??? Thanks

[nitro23456]

My feed and return are 15mm under the floor boards but 22mm from boiler and primaries and thus are reduced somewhere after the motorised valve.

Lift a floorboard and take a look.