In article l.net,
Dave Liquorice wrote:
A lot of programablale stats time switches etc are "volt free" on the
contacts ie. not connected to the devices supply (mains or battery)
internally. The switching bits are mains rated so the actual control
circuit can be low voltage or mains.

Mine had a long lived battery. With a clever type of relay (taking a very
small current from the battery) to switch the boiler.

Although I already had a neutral and earth run to the thermostat location
(triple and earth)

--
*It's o.k. to laugh during sexŒ.Œ.just don't point!

Dave Plowman London SW
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