So I have the HR92's set to control the heating zone valve as the old controller did, the valve opens and turns on the pump and the boiler, and when it closes, it switches off the pump and boiler all as it should.
However, is there any advantage in fitting a third BDR91 relay to control the boiler separately? I worry (probably unnecessarily) that the boiler can be running flat out and when demand stops the valve closes and it shuts the boiler and the pump off when there is a lot of heat left in the boiler. Can or is the Evohome capable of switching the boiler on/off and leaving the zone valve and pump to run on as and when necessary? I do not have any type of pump overrun system and there is a bypass to 2 radiators with no valves fitted.