Our combi is losing pressure about every 5mins. & it does not repressure itself back up. So, we have to re-pressure it why is this so bad to lose this amount of pressure so quickly? It is doing this every day all day & night losing pressure. The combi is at least 4 years old. Yes we did have a recent bad winter aswell where we had a few of the outside pipes burst. But, they don`t connect to the boiler. This has got us really stumped!!! What can we do about it? It is set about 1.4 to 1.7 & drops right down to 0 in a very short space of time. PLEASE HELP!!!

Keith, January 2011

I had a similar problem with my Worcester Bosch Heatslave boiler. Check your overflow pipe. It is likely that pressure is building owing to a blocked pipe to the expansion tank. When this occurs the sealed central heating system jettisons water when the pressure builds during heating. If it cannot expand into the expansion tank it will reduce the pressure by venting it via the vent pipe. Put something under this pipe to collect any water to prove that this is happening. Simple to cure. Remove flexible pipe to expansion tank and remove blockage. It worked for me.

ChrisD, January 2011