On 26/05/2014 17:13, RJS wrote:
On Sunday, 25 May 2014 11:47:41 UTC+1, wrote:
Hello



I wonder if anyone can answer a plumbing question. I just changed the potable water expansion tank for my unvented water system. All seems to be working fine, but I am wondering if I have a missed a step.



I have a zilmet 24l tank pre-charged to 50 psi sitting at the highest point in the system. Obviously the tank was full of air when I first connect it up and I am wondering if I need to bleed the air from the water side of the membrane to fill it up with water? There seems to be no way to do it, and no suggestion it should be done, so I will presumably just contract legionaire's shortly?



Any comments appreciated!



Thanks

Darren

Sorry if this a stupid question Darren: is it essential that the expansion vessel is at the highest point of the system? In my pressurised system - admitedly only for CH - the pressure vessel is not at the highest point in the system and any air is bled from the towel rads and attic rad. So if you are using the PV to pressurise a water system, shouldn't there be an air bleed point higher than the PV?

Richard



There has to be an air bleed somewhere ... as I mentioned on my install
the air bleed is an 'auto vent' on top of Thermal store ... not the
highest part of pipework but it works as air does end up there.

Follow the pipe run you will (or should) find either an auto air vent or
a manual bleed screw.


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UK SelfBuild: http://uk.groups.yahoo.com/group/UK_Selfbuild/