low SHR minisplits
charles3
| Posted in Mechanicals on
A recent GBA article by Scott Gibson states, “Peter Yost, GBA’s technical director and a Vermont-based building consultant, says there are high-performance minisplit heat pumps with SHRs of less than 70%.”
Can anybody list such equipment?
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Replies
Mitsubishi FH18 is listed as 0.69: https://nonul.mylinkdrive.com/files/MSZ-FH18NA_MUZ-FH18NA_Submittal.pdf
Note that the listed SHR is at only at one operating point - probably one you rarely use. It may be far worse at more common operating points.
Jon R, is there a standard operating point at which SHR is measured?
I have an application where I want low SHR and I've been looking at the Chiltrix air-to-water heat pump. It's designed to be installed like a mini-split, with indoor heads, and an outdoor compressor, but the fluid flowing is chilled water instead of refrigerant. You can adjust the SHR by adjusting the water temperature, water flow rate and air flow rate in the head. Unlike a mini-split or conventional HVAC you don't have to worry about the evaporator freezing or "slugging" the compressor if the coil temperature is too low.
Chiltrix makes a controller they call the "Psychrologix" controller that allows you to set a target temperature and humidity and the controller adjusts the water temperature to modulate the SHR to hit both numbers.
I have no first-hand experience though.