Mitsubishi Minisplit Minimum Cooling Capacity
kineticcanine
| Posted in Mechanicals on
I have been looking at specs on Mitsubishi minisplits. For the FS model, a unit rated at 9,000 Btu/h has a minimum cooling capacity of 1,700 and a 12,000 has 2,500:
http://www.mitsubishitechinfo.ca/sites/default/files/SH_MUZ-FS06_18NA%28H%29_OBH873B.pdf (see page 4)
However, for the GL model, a 9,000 has 3,600 and a 12,000 has 1,500:
http://www.mitsubishitechinfo.ca/sites/default/files/SH_MU%28Y%29%28Z%29-GL09_24NA%28H%29_OBH733J.pdf (see page 4)
I’m wondering if the typical rule of “do not oversize” applies in this situation. Assuming a 9,000 minisplit would be correctly sized for the area I will be cooling, would it be better to get a 12,000 GL model instead of a 9,000 GL model because of the minimum cooling capacity?
I did contact Mitsubishi and the person I talked to was surprised that the bigger unit had a lower minimum cooling capacity but he seemed to think that it isn’t a typo.
I would love to get some additional insight on this before I make any decisions. Thanks very much!
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Replies
If you need dehumidification from your mini split, be sure to compare the minimum cooling capacity to the minimum fan speed. I think that you will find both the FS and the GL 12k have too many cfm/btu to actually be doing much dehumidification at their lower operating capacities, whereas the GL 9k might be expected to dehumidify reasonably well if operating at its minimum capacity and fan speed.
oh no! another spec to consider! ha ha!! thanks for mentioning that as i am hoping to get reasonably good dehumidification as well as cooling. i will definitely look into it.
: )
the minimum fan speed for the gl model is the same for the 9,000 and the 12,000 (145 cfm for cool dry and 109 cfm for cool wet):
http://www.mitsubishitechinfo.ca/sites/default/files/SH_MS%28Y%29%28Z%29-GL09_24NA_OBH732D_0.pdf (see page 6)
as an aside, this is also the case for the fs model (137 cfm for cool dry and 117 cfm for cool wet):
http://www.mitsubishitechinfo.ca/sites/default/files/SH_MSZ-FS06_18NA_OBH872A.pdf (see page 5)
so im still not sure why the 12,000 has a lower minimum cooling capacity than the 9,000 and if i should get the 12,000 even if it is technically oversized. i really hoped the specs on the 9,000 would be better as the mitsubishi is a lot more expensive than other options.
any other thoughts greatly appreciated!
: )