Combi boiler system losing pressure

[peteh20]

you can put a presure guage on a rad presure your system up (both guages will read the same) then isolate the system out using the isovalves under the boiler leave overnight any leak on your system will be shown on the rad guage a boiler leak will show on the boiler guage. I ve had a leak on an auto air vent within a combi which evapourated within the boiler took a while to find it. doing this test will at least make sure your looking in the right place good look

 

[coldwrench]

you can put a presure guage on a rad presure your system up (both guages will read the same) then isolate the system out using the isovalves under the boiler leave overnight any leak on your system will be shown on the rad guage a boiler leak will show on the boiler guage. I ve had a leak on an auto air vent within a combi which evapourated within the boiler took a while to find it. doing this test will at least make sure your looking in the right place good look

I would like to do that but I already tried to close them when changing the pump. They wouldn’t turn easily through 90 degrees and leaked when returned to the open position. Fortunately, the leaking stopped after 1~2 days. The way the original piping was installed means fitting separate valves is not very easy. It’s probably easier to follow the heat exchanger route, but I will certainly give that suggestion some more thought.

 

[Blackcatgas]

I would like to do that but I already tried to close them when changing the pump. They wouldn’t turn easily through 90 degrees and leaked when returned to the open position. Fortunately, the leaking stopped after 1~2 days. The way the original piping was installed means fitting separate valves is not very easy. It’s probably easier to follow the heat exchanger route, but I will certainly give that suggestion some more thought.

Tighten up the packing glands if they leak.