I have a problem with my boiler . Its a Ravenheat RSF 820/20t
The boiler itself seems to work as it should ie hot water and radiators work OK, but after you turn off the hot water tap the boiler makes a rumbling noise .
i've also noticed that i've had to top the system about every 3 - 4 weeks.
Had a plumber come round and he suggested one of three things - faulty fan (has been changed but problem still exists), faulty gas valve or faulty water pump
any help would be appreciated before I splash out any more cash
lak

The boiler itself seems to work as it should ie hot water and radiators work OK, but after you turn off the hot water tap the boiler makes a rumbling noise .
i've also noticed that i've had to top the system about every 3 - 4 weeks.
Had a plumber come round and he suggested one of three things - faulty fan (has been changed but problem still exists), faulty gas valve or faulty water pump
any help would be appreciated before I splash out any more cash
lak
