Mini-Split keeps cooling below setpoint – why?
nuthin2fancy
| Posted in General Questions on
My eight-year old Mitsubishi mini-split has be the definition of reliable for my well-insulated 430 sq ft shed in Wisconsin. Until today. Now, it keeps cooling regardless of the setting on the factory remote unit.
I learned early on to point the remote at the unit when adjusting temperature – that’s not the cause in this case.
Turned the unit off for a bit then back on. No change.
There are no indicator lights on the unit – everything appears normal, it’s just overdoing the cooling.
Searching the web turned up very little on this. Lots of ‘not cooling’ articles, but not much on too much cooling.
Has anyone else run into this?
TIA
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Replies
Sounds like a bad indoor air temp sensor. Those sensors are extremely reliable but sometimes condensation can get on it which can cause corrosion issues. Try to set it to heat and see what it does, might help narrow down what the issue is.
Thanks for the suggestion. I set the unit to heat and the wall thermometer went from 68 to 73 (F) in about four hours. Ambient is currently mid seventies and sunny on the way to a forecasted high of 83. The building has a full southern exposure.
I turned the indoor unit off and will do more research online about the sensor. Initial searches aren't turning up a great deal. My main concern at the moment is keeping humidity from getting too high.
Any resources or references are greatly appreciated.