hi i have replaced some old radiators from singles to slighty smaller doubles, but have a problem that the new rads i fitted the flow pipe runs hot but the return pipe cold and i can only get heat to a few rads at once,
my older rads the other end of the house are cold except for one which has the same problem flow pipe hot return cold.
i know there is no sludge because i used x400 sludge remover and have flushed the system through three times i also have replaced the pump that feeds the heating because old one had ceased working!
could it be that because the rads are doubles i would need a bigger pump or are there other underlying problems.
p.s the pump air vent and rads have all been bled no air in system!!
this is really getting to me now!
it is a feed and return system through 22mm pipe teed to 15mm run through old potterton oil boiler.
my older rads the other end of the house are cold except for one which has the same problem flow pipe hot return cold.
i know there is no sludge because i used x400 sludge remover and have flushed the system through three times i also have replaced the pump that feeds the heating because old one had ceased working!
could it be that because the rads are doubles i would need a bigger pump or are there other underlying problems.
p.s the pump air vent and rads have all been bled no air in system!!
this is really getting to me now!
it is a feed and return system through 22mm pipe teed to 15mm run through old potterton oil boiler.