HomeKit How to choose controller for Fujitsu Air Conditioner?

[scania471]

We have a Fujitsu AOYG18LAC2 outdoor unit which is controlled with Siemens RDG160T. I would like to make it smart for my parents but I don't really know what kind of thermostat I need to look for.
Can somebody help me in this situation? Should I check the wires in the controller or what should I do?

 

[cynics]

Typically referred to as ductless units they aren't exclusive to not have ductwork. The thermostat is going to be wired to the indoor unit, do you have the model number available for that? Depending on installation this can often times be difficult to access.

Do you know if there is an IR remote or the indoor at least has the capabilities for receiving an IR signal?