Vokera Compact 28 Expansion Vessel

[vokeraques]

Hi there,

On the Vokera Compact 28, there is a small valve on the top of the expansion vessel. I'm just wondering when it should be open / closed ?

Should it be open when repressurising, and closed once the system is pressurised?

Also, what should the normal pressure of the system be when the combi is turned off and cooled down? Should it be 1 bar?

Thanks for any tips..

 

[Boiler medics]

Hi in reply to your post regarding the valve on top of the expansion vessel this is a shraeder valve and is for connecting a air pressure pump to introduce air pressure to approx 1 bar (14.5 psi) only when the boiler is turned off and completely drained of water.It is very important that this charge pressure is maintained in the expansion vessel and should be checked every time a service is carried on the boiler . The water pressure shown on your boilers pressure gauge should read min 1 Bar when the boiler is cold and will rise accordingly when the boiler is operating to show an increase depending on the expansion volume taking place in the heating system water.On an average heating system with 7 to 10 radiators you may expect to see the needle on the gauge rise to no more than 2 bar pressure when the boilers maximum temperature of 82degrees centigrade has been reached. hope this helps you out . Boiler medics engineer

 

[vokeraques]

Hi there,

Thats great. Thanks for the information. That is clear now and I will make sure the engineer checks this when I get it serviced.

Thanks a lot!