Carrier Infinity ductless minisplit has excellent specs
lance_p
| Posted in General Questions on
Has anyone checked out the Carrier Infinity minisplits? They’re advertising a 3/4 and 1 ton unit that respectively have 42 and 32 SEER, 15 and 14 HSPF, and are rated to operate to -22F (-30C):
https://www.carrier.com/residential/en/ca/products/ductless-systems/38mpra/
On paper at least they look like formidable competition for the best from Mitsubishi and Fujitsu. Thoughts?
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I believe it is "badge engineering" but I can't remember what the underlying tech is.
Previously Carrier ductless units had all of the features of a re-branded Gree, but that changed about a year or so ago.
The new ones look a bit like Samsung's Smart Whisper - Max Heat Series compressor units but I don't know for sure. The alleged efficiency specs for the Carrier units are better than the Samsungs, eg:
https://dvmdownload.com/upload/product/153/download/AR09KSWSPWK_AR09KSWSPWK%20Max%20Heat%20Submittal.pdf
The claimed SEER ratings is what stood out to me. At 42 and 32 they are quite a bit more efficient than anything I'm aware of.
However, looking at their data sheet:
https://www.utcccs-cdn.com/hvac/docs/1009/Public/06/38MPRA-01PD.pdf
It would seem their COP values are relatively low? I mean, at 17F outdoors the best reported COP is 2.36 for the 1 ton model, and that's only with an indoor condition of 59F. At 71.6F (closer to where I'd set it) the COP drops to 2.14. Is it just me, or does this not seem like class leading efficiency? Reported HSPF is 14 for this model and 15 for the 3/4 ton.
The modulating range is pretty poor. It doesn't seem like the numbers are likely to add up to better performance in the real world.
I do like the low heating cut out temp though (cuts out at -35F, on at -25F). That's where Fujitsu seems to beat everyone right now. When it's that cold I don't really care what the output is, as much as I care about making enough heat to keep pipes from freezing. Where I live it's conceivable I could get a 2 or 3 day stretch below the Mits cut out temp, making some sort of backup heat necessary to protect the house.
Agreed. Nice to know it's not going to shut off completely on the coldest night of the year.
I also noticed the lackluster modulation range. I have no idea how SEER and HSPF testing is done, but based on the fact minisplits can have such impressive numbers I would tend to think the tests must favor equipment that modulates well? That's pure speculation on my part, and really doesn't correlate to these units testing so well with their limited range.
As I understand it current HSPF tests don't really address the modulation aspects very well. The manufacturer can pick an output level, and test the efficiency at that chosen output +47F & +17F. It's more complicated than that, but that's the gist of it.
Here's a document that tries to make sense of the HSPF:
https://aceee.org/files/proceedings/2004/data/papers/SS04_Panel1_Paper08.pdf
Unfortunately I don't have time to study the whole thing. The conclusion reads:
"The results of this study show that there are a number of factors that can have a significant impact on the seasonal performance of a heat pump..."
"The actual climatic conditions and the building load play a major role."
"For current construction, which often results in homes that have balance points in the 50s, the standard calculation procedure appears to systematically overestimate the seasonal efficiency."
"While it does not seem practical to stop applying HSPF values to heat pumps, it is important to understand the limitations of these values. They can indicate that one heat pump is more efficient than another, but to assess how much better for a particular application requires a more detailed calculation."
So why is this so complicated? It sounds like the chosen test parameters can be different for each unit tested, which is nothing short of BS and makes the HSPF almost completely meaningless. Why not have a standard test procedure that varies the load based on the capacity class (tons) of the unit, and report this for individual climate zones?