Edwin (and others),
Nice to see you all like to use that Gateway, but I have not read here for what function precisely ...
I dived into this Opentherm stuff because I happen to have installed an Avanta boiler and Celcia20 room controller and quickly decided I wanted to be able to see the real outside temperature rather than those 4 dashes. My own version of a gateway, based on a microcontroller, is operational for some months now; the temperature sensor is connected to the gateway and when the Celcia20 requests the outside temperature from the boiler, the gateway does not pass on the response from the boiler but instead injects a frame containing the temperature, thus answering the request from the Celcia20. The Celcia20 is really the master in an Opentherm environment and the gateway must "behave itself" and only speak when it really knows better than the boiler.
So, it depends on the functionality of the master (=room controller!) and the slave (=boiler) whether the gateway can do anything useful in your particular case.
The Celcia20 does e.g. also ask for a possible Remote Room Temperature Setting. Maybe that's what you want too? If the gateway lets such request/response pass unchanged the Remote Room Setting functionality of the room controller won't work. However, when the gateway has been told, e.g. via a modem link, that the room temp should go to 25
the gateway will alter the response from the boiler and answer the Celcia20 of the desired temp. that will override the local programming. That particular function happens to be one that I'm experimenting with now.
I hope this write-up is useful for you.
Arjen
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