You have to make sure your garage heater can accept that type of therm.
The opener will definitely work.
For something quick and dirty and way less expensive and if your garage heater is pluggable, then you can use a tilt sensor with temp and a power plug.
Just cut power to the heater once the door is opened.
You can use the garage controller to figure out up/down status of the garage door but what about a Z-Wave or Zigbee relay to interrupt one of the two thermostat wires to your dumb thermostat? The only time the heater starts is when the circuit is complete.
Can you expand on this a little? does the Zigbee modem have to be connected to a PC the entire time? I’m trying to do some quick reading on Zigbee right now. The goal is the same though. Low voltage thermostat and a chamberlin myQ garage. Kill the heater when the door is open since gas bills are something that my wife and kids believe are non-existent.
Thanks