Quote:The idea was to have the two in series - should be o.k. The clever one in the living room, and the other by the boiler as a back up.
That would prevent a high bill in the event one stat fails in the ON position.
However it make it more likely you would have a burst pipe. Because you need both stats to work in order to turn the heating ON. If either stat fails in the OFF position the other cannot turn the heating ON because they are in series.