Another question for plumberists...

If it only goes up to 5 on the gauge then 4 is quiet high.it sounds like there is to much pressure in the vessel,what pressure have you got when the system is cold

 

Is it actually shaking on the wall?

 

Does the vessel have an isolating tap or valve if so is it turned on

 

It's Chernobyl all over again

 

Just for reference as I'm not a plumber, but we had endless amounts of trouble earlier this year and the Valient bloke told me that it should sit around 1.5 bar and ours went hot cold and it was a blocked secondary heat exchanger (combi boiler) although I suspect your house is too big for a combi?

 

I think the safest thing to do is drill a hole in the vessel, then screw it a self tapper.

If you think the pressure is getting too high then you can unscrew the self tapper and release the pressure.

If pressure is too low, hitting the vessel with a lump hammer will decrease it’s internal volume and theoretically increase pressure.

Make sure the self tapper is tight. Wrap some electrical tape around it for an air tight seal.


Do the above whilst whistling a jaunty tune, interspersed with loud singing of the wrong lyrics to an Elvis song and get your arse crack firmly on view, the boiler will be lulled in to false sense of security brought about by your plumber like appearance.

 

Combi shouldnt be anywhere near 4 bar.

 

That's exactly what they said at Chernobyl.

 

When a plumber is in the loft ..
furiously pumping away..

Their not servicing the boiler.

 

Have you tried standing in front of it, sucking your teeth?

 

I had almost the same problem traced it to the expansion vessel had lost its air.

 

It’s getting boring