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Roger Mills
 
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Default Draining a central heating system with no drain point


"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?

Thanks

D


If you want to get *all* the water out, you'll need a drainpoint at the
lowest point - under the floorboards. In my previous house, which had
suspended floors downstairs, I fitted a stop-tap under the floor (accessible
through a small flap in the floorboards) with the output pipe going out
through a vent brick - so that I could collect the water outside.

The pipes need to be completely dry to make soldered joints - but this
doesn't apply to compression fittings nor, I suspect, push-fits.

Roger