Hi I/ve got a worcester heatslave 15/19 oil boiler, when I put the heating or hot water on the boiler pressur rises to about 2.5bar from the 1 bar its set at why?
Thanks
when you HEAT water it EXPANDS, the system is sealed the now HOT water raises the pressure in the sealed system, pressurizing the system also raises the boiling point of the water inside.