"Lobster" wrote in message
news
Jan Larsen wrote:

I tried to turn the square bit, nothing, then turned the collar thing
underneath the square bit, got a bit of a dribble but not much, after a
few more turns I noticed water emerging from underneath the collar and in
fear of water emerging at considerable speed in directions other than my
original intention and the swift administration of the mother of all
bollockings by the wife I decided it best to turn the collar the other
way and ask first.

You're doing it right; there's nothing particularly complicated about it.
Presumably yours is jammed internally or something. You certainly
shouldn't need to undo the knurled collar.

David

I would expect that the rubber washer has partially decomposed and is stuck
in
place. There is no completely mess free alternative way - what I try to do
is
get an identical looking drain valve and take apart to understand what gets
stuck,
get one or two similar washers as spares, (ensure you have turned off all
the radiators
at both ends and obviously the feed) and take out the valve bit completely,
with a
wet and dry vacuum cleaner running and an able helper.

Dig out the old washer.

Obviously, there will be increasing amounts of water emerging, so the
machine
may have to be emptied 2 or 3 times. You should be able to hold back the low
pressure
water with a finger and thumb over the outlets whilst helper empties the
machine.

Or you could empty the system in the same way by loosening a connection with
the
vacuum cleaner underneath.

With the old rubber washer, out select a washer that seems to be the best
match
for the mechanicals, possibly about 8 mm diameter with a central hole, and
refit with this.

Maybe fit a complete new drain valve ? - easy if compression !

Hope this helps.

Nick