I am about to start my new mini-project and I want to get some feedback from the community to drive in the right direction
The goal: To be able to control the central HVAC system in my house via openHAB 2…
Hardware to be used:
- Hoval TopGas condensing gas boiler model TG-45
- Hoval TopTronic® T controller (installed on the boiler) Key Module 7 (2 mixing circuits, buffer storage unit and solar plant)
- 2 x Hoval RS-OT room station (installed in 1 room)
- 7 x Siemens RDF-110 Room thermostats (one in each of the 7 rooms in the house…but…not integrated with the Hoval System )
The Hoval Boiler has an OpenTherm interface (2 wire bus system on connection pins #30 & #31) and I am planning to use this OT interface to be able to control the boiler directly from OH2.
I have found that there are many OT Gateways available from the manufacturer (Hoval), including a OT-KNX gateway as well as an Ethernet Gateway…
Additionally, I found another option from theben.de: https://www.theben.de/en/Products/Home-and-Building-control/KNX/System-devices/KNX-OT-Box-S
I am planning to use this Gateway to interface OT to KNX and from there, use the KNX Binding in OH2 to control the Boiler.
Since there is no OpenTherm binding available (correct?)… I believe that I will need to use an intermediate translation protocol to achieve my goals…
More news soon as the project develops (of course…expect a full write-up at the end of it :))
Ps: I found some old info here: https://groups.google.com/forum/#!topic/openhab/_hxrvt6D5t0
Ps2: Another way (instead of OT->KNX->OH2) would be: (a) http://otgw.tclcode.com/ + (b) https://github.com/githubcdr/opentherm2mqtt… Opinions on this path?