Salus Programmable Thermostat RT500RF

[ianniann]

The frost stat on the boiler is a remote possibility, just because of how long it takes for these things to cool down. My boiler is in an integrated garage, the part of the house it is attached to is unheated, and I don't think the frost stat has ever kicked in.

I'm going with the interference idea. These are usually just installed on the default channel so any neighbour that has one is very likely to be able to switch your boiler on and off. Change the channel and see if it helps. Of course if you're on a farm miles from the nearest habitation, this might not be the case. Newer (and more expensive) controllers use a more complex digital handshake that avoids this problem.

 

[PullerGas]

With most programmable thermostats the important thing to remember; there's no ON or OFF, only temperature settings.
A set-back temperature of 5degrees can still come on in a cold night.

Salus do a 'dumbed down' version of control instructions for the hard of thinking. If you speak to them just say a Dick Puller said to call.