On 5 Apr 2004 16:13:32 -0700, (Lobster)
wrote:

I've got a plumber in doing some jobs for me at the moment, including
fitting some new radiators to an existing system, which has a combi
boiler and 22/15mm copper pipes throughout. I left him to it this
morning and came back to find he'd installed a rad using 10mm
microbore; he'd put the 15mm TRV and lockshield valve which I'd
supplied to one side, and bought his own 10mm kit instead.

I am admittedly predjudiced against microbore as it's harder (IMO, for
me) to fit, and I believe more likely to block;

Not really. If the system is neglected such that there is sludge
build up sufficient to clog microbore then it is going to be expensive
quite soon.


so I was a bit hacked
off with this, especially as there was no problem at all with access
to existing 15mm pipework under the floor. He'd simply fitted lengths
of microbore to the ends of the flow and return 15mm pipes using
reducers.

When quizzed, he said it was because radiators "work better" with
microbore; that's as much as I could get. The guy is very
uncommunicative and I find difficult to talk to, but he's reliable,
good value, and does a good job, and I don't want to make an issue of
this unnecessarily. But before he fits any more rads for me can
anybody tell me if it's possible there is any truth in what he's
saying?

The one thing that you can say is that it makes the control obtained
by the lockshield valve a little more fine-grained, simply because the
flow is reduced slightly in comparison to 15mm. However, on a short
length of 10mm this will hardly be noticable.

Other than that there is no reason not to mix and match microbore with
15mm provided that sizing is adequate - but that applies to 15mm as
well.






Thanks
David

..andy

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