Hi,
I'm trying to understand why or what I'm missing in the seemingly drastic difference in both HSPF and COP (particularly at 17F) listed in the submittals from Mitsubishi for two 2.5 ton heat pumps using the same air handler, one using their Hyper Heat technology and one standard, specifically:
SUZ-KA30NAHZ (Hyper Heat) & SVZ-KP30NA vs. SUZ-KA30NA2 & SVZ-KP30NA
The -HZ combination lists SEER: 15, HSPF (IV): 9, COP (47F): 3.9, COP (17F): 2.0
The -NA2 combination lists SEER: 18, HSPF (IV): 13.6, COP (47F): 4.2, COP (17F): 3.22
I was expecting them to be similar, but the difference in HSPF seems huge, as does the low temp COP, and it's affecting my calculations of an energy budget. These are from the documents from Mitsubishi and agree with the values used in a heat load calculation from a contractor. Mitsubishi's customer service was not helpful, although I don't blame them - they're used to fielding more of sales questions. I'm not an HVAC pro, but I am a physicist and was hoping some give me a technical explanation for this difference. Is it in how they're determined somehow? Since the Hyper Heat technology is meant to give full capacity at a much lower temperature, is that folded into this somehow? For example, both are given at "maximum capacity", and that of course is much greater for -HZ at 17F (32k) vs. -NA2 (21.4k). Would the COP for -HZ be much higher at 17F if it were determined at 21.4k output? I don't care about SEER so much, but that's pretty different as well.
I'm sorry if this was long and I hope someone can see the problem I'm having. Mitsubishi's newer technology appears to be much less energy efficient at more typical operating temperatures for the same size heat pump using the same air handler and my intuition is that that has to be wrong, but I don't see how.
Thanks for any input,
Matthew Brewster
I'm trying to understand why or what I'm missing in the seemingly drastic difference in both HSPF and COP (particularly at 17F) listed in the submittals from Mitsubishi for two 2.5 ton heat pumps using the same air handler, one using their Hyper Heat technology and one standard, specifically:
SUZ-KA30NAHZ (Hyper Heat) & SVZ-KP30NA vs. SUZ-KA30NA2 & SVZ-KP30NA
The -HZ combination lists SEER: 15, HSPF (IV): 9, COP (47F): 3.9, COP (17F): 2.0
The -NA2 combination lists SEER: 18, HSPF (IV): 13.6, COP (47F): 4.2, COP (17F): 3.22
I was expecting them to be similar, but the difference in HSPF seems huge, as does the low temp COP, and it's affecting my calculations of an energy budget. These are from the documents from Mitsubishi and agree with the values used in a heat load calculation from a contractor. Mitsubishi's customer service was not helpful, although I don't blame them - they're used to fielding more of sales questions. I'm not an HVAC pro, but I am a physicist and was hoping some give me a technical explanation for this difference. Is it in how they're determined somehow? Since the Hyper Heat technology is meant to give full capacity at a much lower temperature, is that folded into this somehow? For example, both are given at "maximum capacity", and that of course is much greater for -HZ at 17F (32k) vs. -NA2 (21.4k). Would the COP for -HZ be much higher at 17F if it were determined at 21.4k output? I don't care about SEER so much, but that's pretty different as well.
I'm sorry if this was long and I hope someone can see the problem I'm having. Mitsubishi's newer technology appears to be much less energy efficient at more typical operating temperatures for the same size heat pump using the same air handler and my intuition is that that has to be wrong, but I don't see how.
Thanks for any input,
Matthew Brewster
source https://hvac-talk.com/vbb/threads/2227333-Confusing-difference-in-Mitsubish-Hyper-Heat-vs-standard-HSPF-and-COP?goto=newpost
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