New System - Help me with my shopping list

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I have a Vailliant Ecotec 637 boiler going to a EPH T47 controller controlling 3 zones (top, middle and lower floor of the house) plus HW.

There are then three very flakey Honeywell wireless thermostats.

It's never worked well so hoping to update my system but struggling to know what to do (and how).

Can I just replace the controller with a Tado wireless starter kit and then get more wireless thermostats?

There a Honeywell valves for each zone - these go to a electric box that the receivers for the thermostats also go to.


I also have a separate wired thermostat for wet UFH in the kitchen - 4th zone!


Any help would be greatly appreciated.