Replacing Myson MPRT with Wired Tado – Second Wireless Zone Compatibility and Setup Questions

whfi

Hi everyone,

I’m planning to upgrade my thermostat setup and recently purchased the Tado Wired Smart Thermostat Starter Kit V3+ to replace my wired Myson MPRT (in the living room).

The wired Myson is currently not working and controls the heating for the living room, kitchen, hallway, and bathroom.

In addition, my bedrooms are controlled by a Wireless Myson MPRT, which still functions properly.

Here are my questions:

1. Once I install the wired Tado thermostat, will my wireless Myson MPRT in the bedrooms still work independently? I suppose the new Tado wired thermostat will only control the living room, kitchen, hallway, and bathroom but not the bedrooms.
2. If I decide to replace the wireless Myson MPRT in the bedrooms with Tado, which Tado kit or devices should I purchase to achieve this?
   (Add-on Wireless Receiver, Add-on Smart Thermostat or the Wireless Smart Thermostat Starter Kit V3+?)
3. Another idea. Would it be easier to change dual zones into single, and all controlled by the wired Tado?

For reference, my boiler is a Potterton Promax Ultra Combi.

Thank you for any advice or recommendations!

policywonk

No an easy answer. Need to have some more info.
1. Do you only have two central heating zones? Are all the thermostats hard wired to motorised valves?
2. Presume you've realised by now out that your boiler was designed to run in Opentherm mode, a system which enables it to throttle up and down according to the heating curve needed and which actually saves money.
3. You can keep your boiler controlled in Relay mode (what Tado calls R01 mode) by replacing the faulty Myson, and configuring the Tado thermostat to operate in R01 MODE which will enable it to maintain compatibility with your existing setup. There is a risk however because both Mysons seem to be programmers as well, which means that your wiring centre seems to rigged to treat central heating as two channels, each of which can wake up the boiler, not just two zones. I recommend you check the wiring at the wiring centre. Or have I got confused?
4. Assuming you have just two zones, to switch to fully opentherm you can
a) keep your existing valves, and replace each Myson with a Tado wired stat to ensure that the motorised valves and open and shut properly, but you would probably need a wireless receiver as well to complete the relationship in opentherm.
b) Or remove the motorised valves and have one tado wired stat talking to the boiler, and over time add smart tado Trvs in each room that's commonly used. Within 2-3 has you'll very likely get your money back in saving.

Your willingness to check the wiring will, I believe, be important.