Avoid Salus. Cheap, nasty with a difficult to understand user interface. TRy EPH. Simple to use and well priced. The EPH Comibipack is wireless "and" Opentherm modulating the boilers burner to the room temperature - where Opentherm is fitted on a boiler of course. It can be used as a simple stat, or a timer as well. Very well priced on the web. Fit one and it conforms to Boiler Plus requirements.