In article ,
Set Square wrote:
Yup. The motor in the valve only takes a fraction of an amp, and 1mm
is rated at 12 amps.

Yes, but don't lose sight of the fact that - in a Y-plan system - the
3-port valve switches the boiler and pump on in some modes, and the
current for that *also* goes through the room stat - so it's not *just*
switching the valve.

We're still talking small currents. A 5 amp fuse is fine for most systems.

--
*The man who fell into an upholstery machine is fully recovered.*

Dave Plowman London SW
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