weird boiler pressure!

[32tybeams]

I have been having to repressurise my baxi combi 80E boiler when its stone cold every morning for a few weeks now. As the pressure is is down to zero. I refill to 1bar. And it stays at 1bar for hours later before putting heating on. needle rises to a steady 2bar. And drops out a small drip from pressure relief outlet on other side of wall. The expansion vessel was repressurised to 1bar during its service about 4 weeks ago and found to be in good condition with no rupture. I've had enginneers out since to try to find out why pressure keeps dropping explaining and showing the small drip from outlet on outside wall. But they keep trying to tell me that i must have a leak somewhere possibly under floor. I would have thought it would make more sense if they would at least change the prv first before having to go down the route of ripping up carpets and floor boards. Strangest thing though! is some mornings now i'm finding i've still got water in there and either don't have to top it up or have to top it up a little. Anybody know whats going on? Thanks.

 

[dcawkwell]

If you are not loosing any water from the pressure relief valve
you have a leak elsewhere.
Just what quantity of what are you loosing from the pressure relief
valve? A few drops aren't going to do it. You are loosing a gallon or two.

 

[32tybeams]

Thank You. if you can work it out! the amount of pressure i'm losing would be when i turn it of at bedtime. about 22.30, its at a steady 2bar then when i get up in morning about 06.40 the needle is at zero. But as i said on some rare mornings such as this morning there was pressure upto just a little below below 1bar. so i didn't need to to refill it.