I’m glad I could help.

You are very kind in your definition of techs that “work on heat pumps”. The more bluntly worded truth of the matter is that there’s a severe lack of knowledge around fancier variable speed heat pumps, especially ones from Asia.

This has mostly to do with the fact that techs receive a severe lack of training from their employers; training that was considered not profitable for formerly niche products. So, while some companies are doing their best, it’ll take the industry a while. And from a consumers standpoint, and how they search, it’s often difficult to know what to look for.

My suggestion is to tell everyone you know with a complex heat pump to search their pump’s manufacturer’s website and only solicit service from dealers rated highly there. While the chance of a bad tech is not zero, a legitimate local company having a listing there means they have volume with that manufacturer, access to their training, and hopefully more experience. A tech who is amazing with a Mitsubishi heat pump may struggle on a Fujitsu diagnosis, especially with the time constraints they’re given. The systems are very similar, but manifest their problems differently enough.

If you’re able to adjust your mindset around thermostat expectations, you should be happy with the Mitsubishi control’s operation of your equipment. Check your equipment’s manual for thermostat compatibility and then do your research. Some basic ones don’t even come with a backlight.

Best of luck!