By addressing its most glaring deficiency, a sub-standard turndown ratio, Mitsubishi has an early lead in the competition for the best heat pump in the post-R-410A era.
Thanks for this early review into the Mitsubishi equipment for the new refrigerant! The subpar turndown is the main disadvantage I've seen with Mitsubishi vs other systems.
I'm curious if you have any comparisons with 1-3 zone single fan condensers, or even form factor changes? (For reference, I'm considering a 2 condenser system for one 1 ducted basement + 2 ducted floors, although still pretty small overall. I doubt I have the ability to get approval for a larger condenser.)
I was a bit concerned about the apparently slightly higher "flammability" of the new refrigerant, especially since installers would just be learning how to install it, curious if you have any thoughts there as well. Am also a bit nervous about waiting too long given those factors and the geopolitical instability + tariffs, but the 410a units seem to be getting removed from the MassSave rebate lists, so there may not be a real choice I suppose...
Not yet, but we'll review the whole lineup & compare it to the equivalent models from other brands this summer as an intern project!
Re: flammability, I wouldn't lose a minute of sleep over it if I knew that the refrigerant lines were properly sealed with no leaks. Good news is, there's an easy way to tell whether it's properly sealed: a pressure test with high pressure holding consistently for 15+ minutes, and a vacuum holding below 500 micron for at least 15 minutes as well, the longer the better.
Every homeowner should be demanding to see this, and we're about to go on a crusade to make this a standard. It's also important b/c if refrigerant is leaking, you straight up should not be paying this contractor.
As for the inherent flammability, aside from leaks, I wouldn't worry. We already have way more flammable gas in the vast majority of homes in the US: natural gas. If you're ok with gas, you should be okay with this.
Thanks for this early review into the Mitsubishi equipment for the new refrigerant! The subpar turndown is the main disadvantage I've seen with Mitsubishi vs other systems.
I'm curious if you have any comparisons with 1-3 zone single fan condensers, or even form factor changes? (For reference, I'm considering a 2 condenser system for one 1 ducted basement + 2 ducted floors, although still pretty small overall. I doubt I have the ability to get approval for a larger condenser.)
I was a bit concerned about the apparently slightly higher "flammability" of the new refrigerant, especially since installers would just be learning how to install it, curious if you have any thoughts there as well. Am also a bit nervous about waiting too long given those factors and the geopolitical instability + tariffs, but the 410a units seem to be getting removed from the MassSave rebate lists, so there may not be a real choice I suppose...
Not yet, but we'll review the whole lineup & compare it to the equivalent models from other brands this summer as an intern project!
Re: flammability, I wouldn't lose a minute of sleep over it if I knew that the refrigerant lines were properly sealed with no leaks. Good news is, there's an easy way to tell whether it's properly sealed: a pressure test with high pressure holding consistently for 15+ minutes, and a vacuum holding below 500 micron for at least 15 minutes as well, the longer the better.
Every homeowner should be demanding to see this, and we're about to go on a crusade to make this a standard. It's also important b/c if refrigerant is leaking, you straight up should not be paying this contractor.
As for the inherent flammability, aside from leaks, I wouldn't worry. We already have way more flammable gas in the vast majority of homes in the US: natural gas. If you're ok with gas, you should be okay with this.