Replacing old Honeywell T40 Thermostat with Tado Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[Aaronsoup]

Hi there,

I'm trying to replace an old Honeywell T40 thermostat with a Tado.

Slightly confused by the change in labels on the two thermostats and can't seem to get it to work.

I have a basic combi boiler with no control box or anything, which was hooked up to a Honeywell T40 with three wires in this configuration:



The wiring diagram for the new thermostat looks like this:



Can anyone put me out of my misery?

[Andywb]

Did you solve this as I have the same issue and wiring configuration in the Honeywell thermostat?