Set Square wrote:
I am considering overhauling and zoning my central heating later this year,
and would like separate control of each rad. I'm looking for motorised
valves which are as small as possible and which will fit on 15mm pipes. The
only ones I can find are 22mm. [Yes, I know I can use reducers - but the
whole thing is still too big].

Does anyone know whether smaller ones are available and, if so, where from?

TIA.

I am planning to do something similar, linking it all into a home
automation system. I was planning to use solenoid valves, as (like you)
I have discounted motorised valves as too big / unwieldy.

I'll probably buy mine from Asco (www.ascojoucomatic.com) as that is who
we use at work, but there are plenty of other suppliers, including RS
(example part number 439-127)

The only concern I have is the 'clunk' as they switch, but hopefully an
anti water hammer model will avoid that.

HTH,

Chris

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