Pressure Reducing Valve, Rising Pressure

[DIYNovice101]

Hi,

Our plumbers installed a Caleffi Pressure Reducing Valve on our mains supply and I'm wondering if the static pressure shown on the pressure gauge is suppose to rise when the taps are turned off.

We get 2 bars shown when the taps are running, turning off the gauge reverts to around 3.5bars and then slowly creeps it's way up to 5.5 bars over the course of 15 minutes or so.

Is that normal? I thought the valve was suppose to hold the static pressure somewhat?

 

[JimCrow]

No, Look at " Drop tight " Pressure Reducing Valves

 

[fezster]

Some pressure reducing valves have gauge ports for either side of the valve. Make sure it is measuring the reduced side.

Most are now drop tight, but worth checking yours is. Otherwise static pressure will rise.

Also, if you have an unvented cylinder, does the pressure rise coincide with when it is heating? If so, your UV expansion vessel may have failed or needs pumping.