I simply want to move a Radiator 3 foot to the left so its sitting
under a window . But i will have to lengthen pipes to do this , that
is not a problem . My question is i have a combi bolier , do i drain
it down , what do i turn off . Basically what should i do . I had no
problems with my old back boiler , but the combi is new to me . Any
help please .
Firstly, I am not a plumber.....
...however if you have worked with other central heating systems then this
should not be difficult.
You obviously have to turn the boiler off, but then you just have a sealed,
pressurised system instead of a vented one with a small header tank.
Drain down the radiators as normal from the lowest point - you may have to
loosen off a bleed screw from an upstairs radiator to get the water out. Be
prepared for a lot of pressure when you start to drain.
Move your radiator, close all bleed screws etc..
You will, of course, have to add chemicals to the water to protect the
system, but this should be relatively easy with a drained system - look at
Follow the instructions for adding cold water to the heating circuit (on my
boiler there is a tap from the mains built in to the base of the boiler) and
pressurise to the recommended mark (for cold), bleed all the radiators and
away you go!
I don't know if you will have to bleed the boiler - mine is a recent one and
has a self-bleed programme when it restarts after power down.
The professionals should be along shortly to fill in any gaps :-)
No problem in draining down a combi system. Just switch off the power to the
boiler & drain down in the usual way from the lowest drain cock, but let
some air into system by opening a radiator vent or two at a higher level.
If you are going to use compression fittings to make your joints then the
water in the system should hold back on a vacuum by opening the rad valve
(after removing the rad) and catching the small amount of water that comes
out before the vacuum takes hold. Do not open any rad vents when doing it
very easy if the installer has put in an additive filling point as
mine did .It's next to the boiler .
My installer fitted two taps adjacent to the boiler .One to serve the
cold water feed to the boiler and another to drain the system down .