ive had boiler in house now for 4 years.up till now no problems now the boiler keeps firing up as if someone is running the water. it does this continuously. if we take a shower the water will be hot then cold as the boiler is switching on and off. we have heating but the same thing happens. the radiators stay hot as they dont get chance to go cold please!!!! can anybody help

julieb1, February 2010

sounds like faulty diverter valve. the rads will be constantly hot as these boilers have a pre-heat for the water. the water which should be going to pre-heat the plate heat exchanger will be passing into the radiators. the diverter valve cartridge will need to be replaced.

Ian, February 2010