Mini-Split Selection- What would You Do – GreenBuildingAdvisor

My Mitsubishi hyper heat 18k wall mount single head heat pump has [apparently] been leaking for a few years. I finally found a tech that was willing to diagnose the leak (air handler coil) and I am advised that replacing the whole system is the only practical option given current parts availability.

The path of least resistance would be to install another Mitsubishi hyper heat 18k. That is what the contractor I am currently working with has offered. I am hesitant to do this, mainly because my experience with my current Mitsubishi hyper heat unit has been less than ideal:

1. I only got ~7 years out of it before it began leaking.

2. My experience with the local Mitsubishi diamond contractors has been mixed. They mainly seem interested in installing new systems. Ability/willingness to diagnose & repair is limited.

3. Flaky behavior that could not be resolved by contractor (excessive air handler noise, short cycling/oscillations, wide deviations from setpoint).

In terms of what the unit needs to do, cold weather performance is important. The current hyper heat unit has shut down twice (in ten years) on exceptionally cold nights. During the coldest part of the season, my current 18k unit is probably running close to or at full modulation a meaningful percentage of the time. My electricity is expensive so COP at near full modulation matters.  Not using it much for AC.

Some specific questions:

Am I likely to have a better experience with another manufacturer vs. my experience with Mitsubushi ? Any specific recommendations for 18k wall mount, single head systems with cold weather performance comparable to or better than Mitsubishi hyper heat ? If I am going to be replacing this thing every 7-10 years should I be looking at Gree/Midea or other lower cost options ?

Should I buy an R410a unit now while they are still available or should I wait till the next generation refrigerant systems appear in the supply chain ?

 

Would appreciate your thoughts on any or all of these questions…