Draining and refilling system Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[rokeeffe]

Hi all,

I am hoping to move and replace some radiators in my home, but first I need to figure out how to drain and refill the system.

My home is separated into 2 zones - Zone 1 is the old part of the house, comprising a 3 rads on ground floor, 3 rads on first floor, 1 rad in attic conversion. Zone 2 is the kitchen - an extension which has underfloor heating. It is all heated by a combi boiler which is located in a cabinet in the kitchen. There is a 'plant cabinet' separate from the boiler, under the stairs in the old house, which is where the pumps and other things seem to run through for the heating. I am located in Ireland if that is relevant!

I am attaching images of the plant cabinet.

Could anyone help me with the process for draining and refilling this system? If there is any important information that I have left out, or if there are further images that would be useful, please let me know. Any guidance would be much appreciated!

Many thanks,
Richie

[stoneyboy]

Hi rokeeffe,
Short answer - don't even try you'll have problems refilling the system.
General guidance assuming you do not have open automatic bleed valves in the system - turn system off, locate the filling loop, remove the mains connection, release the system pressure through the filling loop. Work on one radiator at a time, lowest one first, and complete relocation before doing the next one, you will need to deal with some water leakage.
When done re-pressurise the system and bleed, bleed, bleed.
Regards S

[rokeeffe]

Hi Stoneyboy,

Many thanks for the response, I really appreciate it!

Unfortunately, I'm not fully understanding a lot of what you said which is probably a bad thing!

When you say don't drain the system, are you saying I can move the rads by closing off the valves, fit the new rad in the new location, run the pipes to it and connect to the old pipes, and in doing that there will be some leakage that I should be able to manage?

How do I determine if I have automatic bleed valves? (I doubt that I do)

How do I remove the mains connection?

It's probably impossible for you to give me a step by step on my specific system but I'd love to learn how to do it!

Thanks again,
Richie

[stoneyboy]

Hi rokeeffe,
When I say don't do it I mean don't do anything, do not move the radiators, stick with a working system.
Automatic bleed valves will probably be anywhere where the system forms an inverted U. Look for something about the size of a small brass tea cup with a plastic cap on top.
The filling loop may be a braided flexible hose under your boiler, one end will be the mains feed, the other will connect into the boiler system. The "nuts" are usually 2 spigot chrome fittings which you can undo by hand.
Regards S