I have unplugged imersion and still same prob. Pump is by the boiler on a pipe going to the tank. There are 4 pipes on the boiler. Hope this helps. Also had a corgi eng out and he didnt have a clue what was wrong.
I have a baxi back boiler and my hot water is constantly on even #when i turn off the timer. any ideas. I have checked the power supply and when its off there is no power on the timer????? Please help.