Mitsubishi mini split dehumidify mode

peakbagger said:

I have had my minisplit for several years and normally used it in cooling mode. WIth the recent hot humid spell I have been running in in dehumidification mode.It still cools the house but it really drops the humidity. I am impressed, I have the fan set to automatic and once I knock down the initial humidity it just idles along.

Worth giving it try if you haven't tried it.

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Dehumidification mode is just a slightly less-efficient cooling mode. It runs the compressor at or near max output (assuming yours is an inverter-driven compressor) and runs the fan at slow speed. This means the evaporator coil (indoor side) is running at it's coolest possible point, which condenses out the most moisture possible.

The only way to dehumidify more than this is to run a larger cooling unit and then heat the air back up after running through the cooling unit, which is incredibly inefficient.

Dehumidification mode is just a slightly less-efficient cooling mode. It runs the compressor at or near max output (assuming yours is an inverter-driven compressor) and runs the fan at slow speed. This means the evaporator coil (indoor side) is running at it's coolest possible point, which condenses out the most moisture possible.

The only way to dehumidify more than this is to run a larger cooling unit and then heat the air back up after running through the cooling unit, which is incredibly inefficient.

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Interesting. I got a very different explanation from the LG booth rep at an HVAC show. I told him I didn't use the "dehumidify" mode because I couldn't figure out what it was doing. No explanation in the owners manual. He explained that "it" measures the incoming inside air temp and adjusts the coil temp to maintain a fixed lower temp. He said it maximizes the moisture removal and still "cools" the output air,... just not so much. Now that's my go to setting for when I'm not home.

The LG rep said it used less energy that way. I wonder if there is a way to keep all the variables the same and measure that?
Your Mitsu unit running running at minimum fan and max compressor sounds like it would use much more energy?

dehumidification mode is different for all makes, even for some of the same make but different year.

I use mine all the time in the summer. It is really amazing.
In 2 days it took the RH from 80% down to 49%. Just incredible system.

Putting one in my new detached garage that I'll be building next year.