pump noise

Hi, my central heating uses a Grundfos UPS 15-50 which is about 15 years old. Over the last few months it has started humming, it's not very loud but in the wee small hours of the morning it resonates through the pipework and wakes me up. The pump is mounted in the middle of a horizontal L...

I previously made a post here about low heat output of the boiler - this has been mostly rectified with a balance however two radiators still only get hot at the top and not at the bottom. Edit: Forgot to mention the boiler is a 26kW Viessmann Vitodens 100-W WB1B :) When the heating/hot...

I have a back boiler in lounge then in airing cupboard a water tank & time clock & pump, over night the heating didn't click off & when I turned it & hot water to off this morning the pump still runs & the water is very hot . I turned it off at plug a few times but it just starts up again I've...

Back for another question. I've had a Salamander CT90 Bathroom Universal pump added into my airing cupboard as part of a main bathroom refit (pressure in the house on my gravity fed conventional heating system was woeful). The pump tees straight off of the hot water outlet from my cylinder and...