Combi boiler central heating

[deso]

Does anyone know how I can drain the systen (to move a radiator). None of the radiators have a drain **** fitted, just those thermostat valves at one end and the normal lockshield valve at the other.

[deso]

I see that the word "drain *.***" has been automatically edited!!

[LATECOMER]

If you are certain no drain **** is fitted anywhere try this. Purchase a self tapping tap,those normally used for diy jobs on washing machines, and drain off through that then replace that section with a compression fitting. But usually there is a drain **** somewhere.

[LATECOMER]

What a puritanical age we live in!!!!!!! drain VALVE then.

[deso]

Neat idea! Thanks Latecomer.

[stanleyman]

That's a good idea I'll have to remember it. You might also have a combined drainoff on the rad valves.

[buildersmate]

I'd be amazed too if there's no drain valve anywhere. In one new house I owned it was to be found right under the backdoor step (house with all 15mm copper pipes into the concrete screed). In another new house with a 22mm pipework system running to a microbore manifold, it was incoroprating as part of the manifold, which was in a downstairs cupboard. You could try both of those places.

If you still can't find it and don't fancy the (good) idea above, you can drain the system by selecting one downstairs rad, closing off the valves both ends (lockshield and thermostatic) then releasing one of the nuts attached to the rad itslef. Be ready to catch about 3 litres of water which will come out of the rad itself. I use empty icecream square containers - ideal. Then undo the other end and remove the rad itself (small bit of water to be caught). Once the rad is off, you can open the lockshield up gradually and let the whole of the system water out in a controlled manner. I've done this with a fitted carpet in place and avoided upsetting she who must be obeyed with any mess.

[LATECOMER]

Hi Deso. Buildersmate has given you some sound advice, and his is the way most people set about doing this task. Just one word of warning though!!! when the radiator is almost empty a black sludge will drain out and this stuff is like black ink and should it get on a carpet then she who must be obeyed will do a bush tucker trial on your gonads. Good luck with which ever way you choose.

[deso]

Thanks for all the help guys - particularly enjoyed "she who must be obeyed will do a bush tucker trial on your gonads" Latecomer. As it happens I've been under the floorboards today (this is my daughter's house btw) and to my delight I found a microbore manifold as described by Buildersmate complete with drain valve and two isolation taps (if that's the correct terminology!), It has 4 x 15 mm pipes entering and 4 exiting - I presume 2 in each direction, so I think I can handle it from here. Once again thanks to you all for the tips.