I have a worcester bosch boiler that is 12 yrs old. This summer the pressure on the boiler shot up over the 2 mark whilst the weather was very hot. As the weather has cooled down the marker has come down again. I have had the boiler checked by BG but they have never heard of the problem. Again today it was colder this morning and the marker had gone down but later rose to around 1.5.
This is all without having the heating on or using the hot water.
This is all without having the heating on or using the hot water.