Smart Thermostat - heating does not start

Chops

Hi. I have installed the Smart Thermostat as per instructions. I have an oil fired Worcester boiler.

Boiler is on constant. Thermostat clicks for demand, but pump does not start.

Any idea's please?

Thanks very much.

Montage

Impossible to say with the lack of detail. Suggests it’s not wired correctly.

Unknown

This content has been removed.