Draining and Re-Filling Combi System

[steve1958]

Hello

I've just moved house and need to move an upstairs radiator. The boiler is a "Combi" and would like to know what the correct procedure is for partially draining the system and re-filling afterwards.
I know I have to use a "filling loop" but am not 100% sure of the method.
Are there any general precautions I should take?
Will I need to drain much water off as there is no expansion tank and therefore no "head"of water?.
Is it possible to overfill or does it automatically stop at 1.0 bar?
Thanks in advance for any help

 

[ArtfulBodger]

Turn off all rads except the one you want to move. Attach hose to drain-off and open. Vent the to-be-moved rad until the hose stops running. You have now drained the pipe work and the one rad.

Move the rad to wherever you want.

Find your filling loop and slowly open and watch the pressure guage on the boiler. Do not let it rise to more than about 2 bar (30lbs). Vent the rad and re-pressurise as necessary but not to over 1 bar. Finish off at 1 bar.

All done.

 

[JPC]

sometimes u find turning off some rads causes more work that u wanted with valves now leaking etc. u do have the option to empty completly by not turning the rads off..but then u need inhibitor puting in the system when u fill up