Feedback on Mitsubishi H2i Hyper Heat Pump
1869farmhouse
| Posted in General Questions on
Will a Mitsubishi H2i Hyper Heat handle sub zero temps? The answer is yes. Mitsubishi heat pump has been running full bore for almost 3 weeks straight with sub zero temperatures and a indoor low of 67 degrees when outdoor temp hit -14.
Maybe someday this will help someone on a Google search, because I was a bit worried myself. But the proof is in the pudding! No affiliation of course, but I’m a proponent after this month.
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Bottom line: With modulating equipment it's important to both read the extended temperature capacity tables and to BELIEVE them!
If you don't bother to even run the load calculations, take a WAG (always oversized), then don't trust the equipment manufacturers' capacity specs you end up with ridiculously oversize equipment that rarely modulates, only cycles, taking a hit in both comfort and efficiency.
So yes, hyperheating mini-splits (Mitsubishi and others) have specified capacities at temps down into negative double-digits F, and those capacity numbers can be trusted for sizing the heat pump to the load (assuming you have a clue what the actual heating load really is.)
I ran a manual J myself using coolcalc and a second paid calculator I no longer remember the name of. It was the best I could do at the time as local resources otherwise are slim to none. I suppose I should have believed the numbers on their face, but I’d never even seen a mini split until I put mine in haha. Thanks for the input Dana.
Out of curiosity, how many sq.ft. are you conditioning, how many floors, rooms, etc.? And what is the rated size of your unit?
3000 sq ft, single pane windows, minimal insulation, 48k btu Mitsubishi Unit.