Zero pressure on red expansion vessel Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[BertyD]

The pressure gauge at the bottom of my red expansion vessel is showing zero. I did bleed some radiators a couple of days ago but got a very low release ( seemed like little pressure coming out). I also tried to add more water to the red tank using the ‘loop’ hose and could hear the water going in. But the gauge stayed at zero. However the boiler and central heating are working fine. Should I be concerned?

[stoneyboy]

Hi bertyd,
It’s probably worth adding more water via the filling loop to see it you get a reading on the pressure gauge. Do you have a pressure reading on the boiler, if yes do not take this higher than 1.5bar.
Regards S

[BertyD]

Thanks for replying. I did add some water previously but only turned the tap for a short time. Few seconds. Should I see an instant increase on the Guage or does it take a minute or two of filling with water?