Condensation inside mini-split housing
Anyone with a Mitsubishi MSZ indoor unit ever have an issue with condensation forming inside the housing case? I’ve had this issue now a few times. The condensate pan and condensate line are both clean and functioning. Condensation appears to be forming inside the housing on surfaces that are next to the cool airflow paths. Looks like OEM has installed some insulation on these surfaces but still condensation is forming as the insulation is wet. I’ve had water tracking down the wall and the other day I had water dripping from the IR lens area. I’ve had the installer already to look at this issue and they couldn’t come up with much.
The unit is on an interior stud wall with no insulation. I did just put some insulation in the 3″ hole behind the unit where the drain, refrigerant, and electric cables come through to stop any unconditioned air from entering behind the unit so if that’s the issue, hopefully that’ll help.
This is a new system installed and first used this year.
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You will get less condensation if you lower the indoor humidity. Most inverter ACs are poor at this, so it is typically done with the assistance of a dehumidifier.
Also check that airflow is unrestricted (eg, a clean filter). Lower than normal airflow causes colder parts.
Hi, Jon R. So is that to say that this behavior is expected?
And yea, a suggestion was to increase fan speed, which would increase airflow. But the system should be smarter than this and not allow the user to select setting that are potentially damaging!
With high enough indoor humidity, I'd expect any AC equipment to have some unwanted condensation. But with normal indoor humidity, I'd expect well designed equipment to have none.