"David Hearn" wrote in message
...
Our central heating system doesn't appear to have any drain points in it
apart from possibly on the boiler (which is about 6' off the floor).
We've
a suspended ground floor with pipework running under the floorboards.
Without actually taking up all the floorboards around the 3 downstairs
radiators to check that someone installed one - I'm a little stuck.

So - assuming for now that there aren't any under the floorboards - what
should I do to drain the whole system?

I'm planning on adding TRVs sometime, so I'll just fit lockshields with
draincocks on when I do that. However I've found a leak on a solder joint
going to a radiator in a room we're decorating. It's been there since we
moved in, but we're going to put down a new carpet - and don't want to
that
if I'm going to need to take it up again to lift the boards to repair the
pipe, let alone if its going to stain the carpet before I do that!
Depending on how I feel - I may well do all the jobs at the same time -
however I just need to get the water out the pipes first!

I know that trying to solder a joint which has any water in it may well
fail - however what about compression joints? Do these need to be
completely dry before making the joint?

No, in fact you can fit them on pipes with water flowing out of them, which
I have taken advantage of several times recently. I'd put an isolating valve
on the wrong way round, so I closed it, closed the valves on the
radiator on the right hand side of it, and then undid the right side. Bit of
water came out. Undid left side, keeping it pressed left, then
swapped it quickly, and did it all back up. Caught all the water in a tray.

Ben