Hi.
Last year I had a new Bosch 15 ri boiler fitted and I've noticed that when the room stat kicks in and the pump starts up, it almost sounds like it has to have 2 attempts to start up before getting going. There are two short bursts of a low buzzing noise (the sort of noise an electric motor might make when under a lot of load) then finally it settles down and pumps 'reasonably quietly' ie a quiet humming noise from the motor and the noise of constantly rushing water through the rads with the very occasional quiet knock which I can't seem to get rid of despite bleeding each rad, the cylinder vent and the new filter many times.
I notice the pumps electrical supply comes from the boiler, is this apparent three stage start up normal ? It's load enough to be quite annoying early in the morning.
Fwiw - the fitter was unable to fit the pump in the same location as before so instead of being under the boiler it's now above the boiler, upstairs under the floor boards (not my preferred location but the valves are there so I can live with that). As I mention there has also been a magnetic filter fitted to the system which I have cleaned out several times. 2 new two way valves were installed at the same time, new radiators and a manual tank vent and everything appears to work normally.
The system was thorough flushed several times over before and after installation.
All advice is appreciated.
Last year I had a new Bosch 15 ri boiler fitted and I've noticed that when the room stat kicks in and the pump starts up, it almost sounds like it has to have 2 attempts to start up before getting going. There are two short bursts of a low buzzing noise (the sort of noise an electric motor might make when under a lot of load) then finally it settles down and pumps 'reasonably quietly' ie a quiet humming noise from the motor and the noise of constantly rushing water through the rads with the very occasional quiet knock which I can't seem to get rid of despite bleeding each rad, the cylinder vent and the new filter many times.
I notice the pumps electrical supply comes from the boiler, is this apparent three stage start up normal ? It's load enough to be quite annoying early in the morning.
Fwiw - the fitter was unable to fit the pump in the same location as before so instead of being under the boiler it's now above the boiler, upstairs under the floor boards (not my preferred location but the valves are there so I can live with that). As I mention there has also been a magnetic filter fitted to the system which I have cleaned out several times. 2 new two way valves were installed at the same time, new radiators and a manual tank vent and everything appears to work normally.
The system was thorough flushed several times over before and after installation.
All advice is appreciated.