Central Heating system won't refill

[coldfused]

In relation to:
//www.diynot.com/forums/viewtopic.php?t=4157
(explained why no pressure because of problem below)

Combi Boiler: E.L.M LE BLANC GVM 4.20

My dad built a conservatory and he moved the old boiler into a new place so that the "flu" was accessible to the outside, we also added a new radiator into the conservatory and DRAINED the central heating system, then added the new pipes and reconnect it to the boiler (in it's new place) now the problem lies here, all the pipes are correctly connected to the boiler but when we try to refill the system, the water does not go into the system, BUT it goes outside (in the garden) through the overflow pipe.

Does anyone have any suggestions please? - Thankyou for any help!

 

[ollski]

you mean when you are filling it up it is coming straight out of the pressure relief valve?

 

[coldfused]

oh, I don't think so - When refilling the system, the water goes straight out through the overflow pipe and not into the radiators

 

[oilman]

Yes, that's right, the pressure relief valve. Unless you have an openvented system, you will have a sealed one, like as not. If water is coming out of the pipe therefore, it will be through the pressure relief valve. It must be stuck open. Rotate the knob anticlockwise a few clicks and see if it reseals.