Mitsubishi Split A/C

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    I am having “disappointments” regarding my relatively new split a/c system. The humidity level is never below 70% and usually higher than that. When I check the drainage pipe (clear tubing)there is never an indication of water running down the tube- maybe a few drops which adhere to the side of the tubing.According to the Mitsubishi site it should be taking out 2-5 pints per hour. I have even tried switching to the dry mode and still no improvement. Anyone else experience this? Any suggestions? Also the air coming out of the compressor is not hot. Many thanks in advance.

    7 Replies

    1. Thank you for the helpful information. I did try running it in the dry mode and it helped “a little”. I do believe the unit had been running non-stop, perhaps indicating that it is not over sized? The installers have finally “hired” a Mitsubishi technician who is coming to look at the installation. Hopefully a end will come to this saga.

    2. If the temperature is lowered effectively but the humidity level remains high then this is a clear sign that the system is oversized. However, in the `dry’ mode those systems should still be able to dehumidify (by lowering the fan speed). The fact that they had to add freon means the installation was sloppy (a well installed system can easily run for close to 15 years without this kind of maintenance). To check whether it is oversized just observe how often it cycles on a very hot day. It should run almost non-stop.

    3. Thank you for the responses. The room temperature is good, it just doesn’t feel comfortable because if the high humidity. The techs just left here again after another 3 hour visit. Interesting that you mentioned the angle of the drainage hose as I had mentioned to them today that I thought it was not angled properly in the basement. They disagreed but changed it in the basement (but not coming out of the unit just down the basement where it connects with the house plumbing)Once again the techs had to add freon as it had leaked out of the flange. Do you have any idea if your humidity level ever makes it to the 50-60% range that Mitsubishi says it should be? Right now it is still reading 70%.

    4. I had the same problem and the tech had to come back. As it turned out, the angle of the drainage hose was wrong. by moving the clear drainage hose he was able to resolve the issue.

    5. I had the same problem and the tech had to come back. As it turned out, the angle of the drainage hose was wrong. by moving the clear drainage hose he was able to resolve the issue.

    6. How is the room temperature? If the unit is oversized it may not cycle enough to remove the moisture.