On Mon, 25 Sep 2006 18:15:21 +0100, Mike W W wrote:

On Mon, 25 Sep 2006 17:44:31 +0100, Roger
wrote:

Where do the feed and return ultimately lead to?

At present, they terminate at one radiator (which is actually not in
Zone 1 or Zone 2) The feed goes into that radiator and the return
comes from it. The boiler does have a by-pass valve too, so that if
all the rads are off, the feed will just by-pass the system and go
directly into the return, whereupon the return water temperature will
shut off the flame and pump. At least, that's how I understand it.

If to the domestic hot
water how is that controlled?

It's a combi boiler. DHW is controlled as per most combi boilers.

I am planning to insert the programmed zone valve in place of the
stopckock shown for Zone 1 (or perhaps next to it).

Replace would probably be easier. I am not sure what continuing purpose
the stop cock could have once you have a motorised valve to control the
flow. To completely isolate the zone so it could be drained down
independently would require a stop cock on both legs.

It occurred to me that I could site the zone valve in the return pipe
for the zone, opposite the stop cock which is in the feed pipe for the
zone. Then I can isolate the zone for draining purposes and plumbing
work etc. Would that be okay?

Zone valves are not bi-directional but you can fit them (the right way
round) in both the flow or return. However they are not intended to act as
absolute stop valves. You would be better to install a pair of full bore
1/4 turn lever valve (also from screwfix) in the heating pipes to the flat
for that purpose.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
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