Honeywell wireless CMT957RF how to

[PetervandePol]

I have a Honeywell CMT957RF thermostat. This thermostat has a sender (in the livingroom) and a wireless receiver in the boiler room switching the heater pump on or off.

I can not figure out how to control this receiver. I know it uses Opentherm, but can not find any data on the wireless RF protocol used.

Does anyone have experience with this thermostat? I would love to integrate it in Domoticz...

[lenard]

As far as I know the situation is:
- The wireless protocol between thermostat and receiver is closed/honeywell proprietory.
- the opentherm protocol is for serial communication on a wired connection so your module communicates with opentherm over the wire to your boiler.

So your options are:
1. Replace your termostat with the evohome wifi version (https://www.kijkvoelbeleef.nl/Honeywell ... ome-Wi-Fi/) so you can use the built-in evohome domoticz device driver. This thermostat should be able to use the existing boiler opentherm module you have. I have this scenario at home.
2. Cut the wire between the honeywell opentherm module and the boiler and implement the opentherm gateway via USB or LAN with the available Domoticz drivers (you can buy it here: https://www.nodo-shop.nl/nl/opentherm-g ... teway.html )

Hope this is clear for you
Lenard.