I am losing water pressure daily and have to keep topping the system up. The pressure valve has been replaced but the problem is now worse. I have insurance but the engineer tells me I must have a leak (they cannot find one). I have no water leaking anywhere that can be found so I have no way of knowing if this is true. In the meantime the problem has been passed back to me and I have no idea what do do next.

SD, December 2009

does the pressure increase to around 3 bar when the heating is on? if so it may be a faulty expansion vessel.

the easiest way to tell if you have a leak on the system is to set the system pressure to 1.5 or 2 bar before going to bed and turning off the flow and return isolation valves.
when you get up in the morning if the pressure has dropped then the leak is on the boiler. if pressure is ok then open the isolation valves again and if the pressure drops the leak is somewhere on the system i.e a radiator or the pipework.

Ian, December 2009