Bungalow-14 Radiator system, Grundfos Pump UPS 1550,Boiler Potterton Prima 50b-Each year less heat reaches the furthest radiators. Now two have no heat at all. If I shut down nearest rads then the further ones get some heat. I have not tinkered with balancing as this was OK in the past. I have bled the system and pump.I can see the pump spindle spinning when I remove brass cap. I have also tried running pump at higer speed.
Do pumps either work or not work i.e can they become significantly less efficient? Does this sound like a need for powerflushing?
Do pumps either work or not work i.e can they become significantly less efficient? Does this sound like a need for powerflushing?
