I have a glow worm swift flow 100 boiler which is 8 years old. I recently moved a radiator after turning it all off and when I switched it back on there is a noise.. a sort of whirringWhining noise everytime the pump speeds up. Is this a result of the bearings on the pump being knackered, or is there some air in the system that i have to bleed out somehow.
The central heating and hot water are working fine, and I have tried bleeding the radiators which do not see m to have excessive air in them at all. The pressure remains constant on the dial.
Any clues on how to stop the noise?
Cheers
Tony