Mitsubishi heat pumps

Posted May 18, 2025 5:52 UTC (Sun) by gutschke (subscriber, #27910)
In reply to: Mitsubishi heat pumps by Cyberax
Parent article: A kernel developer plays with Home Assistant: case studies

At least in the case of my heatpump, I think the thermostat is doing more than just dry contacts.

It can control fan directions or oscillation. It can heat or cool. I believe it can also do "fan only". And it knows if any other unit is currently heating/cooling. If so, it'll avoid cooling while the other unit is heating, or vice versa. I suppose there is some way that you could do this with dry contacts. But I believe it uses a radio control daughter board that then talks some slightly higher-level protocol with the actually head unit.

Mitsubishi heat pumps

Posted May 18, 2025 7:00 UTC (Sun) by Cyberax (✭ supporter ✭, #52523) [Link]

You can buy a regular thermostat and experiment. "Fan only" and switching between cooling/heating are common features. Only the direction and oscillation modes are somewhat unusual.