Engineering Data or Incorrect NEEP?
bmul23
| Posted in Mechanicals on
NEEP lists the minimum capacity of the MXZ-SM48NAHZ2 at 47F at 27kBTU/hr.
https://ashp.neep.org/#!/product/112094/7/25000///0
Mitsubishi at the same test conditions (47F outdoors and 70F indoors) lists a variety of different capacities (engineering manual on mylinkdrive)
Max: 54000 BTU/h
Rated: 54000 BTU/h
75%: 40500 BTU/h
50% 27000 BTU/h
25%: –
Min: 15976 BTU/h
Is the minimum capacity in those conditions 27kBTU/h or 15.976kBTU/h?
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Replies
I reached out to Mitsubishi application for further guidance and will update as more information comes out.
There are too many unknowns on for these VRF systems to say how exactly they will work. Unfortunately the manufacturers don't provide this data or a proper sizing tool. For example, the older Mitsubishi multi split min modulation would increase with each zone you add.
For something like the SM that can work with both the SM specific indoor units and branch boxes, there are simply too many combinations to know exactly what you'll get.
Generally, a right sized multi split with large zones that are above the min modulation of the multi split tend to work well.
P.S. Neep data is not always accurate, I would only use data from the manufacture's spec sheet.