Draining down the central heating

[The Plumber Guy]

Well, it's never simple is it?! I've got to install a couple of radiators in the next day or two and of course the system needs draining down... but there's only one drain valve, soldered in, facing the carpet and so close that I doubt I'll ever be able to open it.

Plan B is - so far - getting a can of freezing spray, cutting the pipe and draining down from one side with a plug on the other. Never used freezing spray so I'll be careful to read the instructions but does anyone have a more sensible plan b? Am I overlooking something simple?

Many thanks all

 

[Guest123]

To drain down the system in the absence of a drain valve, I fit one of those self cutting valves that you get for washing machines and outside tap installations to the pipework on the lowest radiator and attach a washing machine hose to it and run it outside to the drain. Once finished you can replace the self cutting valve with a proper drain valve. A self cutting valve costs about £5 from your local merchants and I always carry a couple. They are good for draining down lots of things and I recently attached one to a live main to take away the pressure so I could work live on a burst pipe as the main stopcock had seized.
I don't like pipe freezing as you're working against the clock and if you hit problems, then a lot of wet house can result.

 

[secret squirrel]

Depends which rads need changing depends on my course of action:

If possible I'll take off a small rad downstairs (hopefully) on a tiled floor then hook up a rad tail to a hose then open the rad valve. Freezing is fine and I do it but I begin to worry a little just incase I hit a problem then your up against time.

 

[dontknowitall]

Plan C or is it D?

Buy a wet vacuum - one tool in the van I just can't do without and when I work with one of my friends (also a plumber) he's always asking me to fetch it. They cost around £70 but should last you at least two years (depending on use of course) and you'll probably use it for over half the jobs you go to, especially emptying WC cisterns - only takes about a minute for that job.

Back to radiators ...

Turn off water supply to heating system.
Find convenient radiator to drain from.
Turn off both radiator valves.
Place towel under whole radiator (or two towels).
Undo bleed valve a little and apply wet vacuum.
Suck.
Stop vacuum when water level below bleed valve.
Undo valve nuts a fraction then do up again.
Undo one valve nut and apply wet vacuum.
Empty radiator.
Tighten bleed valve.
Undo other valve nut (at other end).
Empty radiator.
Establish no water coming out of pipes through valves.
Hook wet vacuum over one end of radiator to capture remaining water and turn on.
Lift radiator and tip towards vacuum.
Turn radiator over and store.
Make an attachment for your hose pipe to valve.
Attach hose pipe and run it outside,
Open valve and drain.
And hardly a drop spilt in the whole process!

Some of this is teaching you to suck eggs but this is how it works for me if I can't find a drain point.

 

[johnmcginty]

if you have never done it i would not recommend freezing , drain down everytime .

 

[Gedpen]

Try hiring or buying an electric pipe freezing kit DO NOT use spray cans, go to freeze master or type pipe freezing into google also using self cutting taps vavles is a good idea.
Hope it goes o.k for you.

 

[fuzzy]

split valve on rad, put a small cup like device underneath to catch droplets of water, take valve off at nut. tighten compression elbow, insert pipe, solder drain off valve on and drain down, easy peesy.
then gently mop up with duster or similar any small drops of water that may have found their way past your pipework whilst working on the new drain off valve. i should get paid for this advice