I have been using a condenser wine cooler unit as a humidor and have been having a problem with the humidity continuing to rise in it. I'm looking for suggestions besides buying a thermoelectric unit.

Specs:
-Outer dims 20x20x32. I don't have the dimensions of the interior but let's just say it is 2 inches smaller and ignore the compressor hump
-3-4 lbs of 65% beads. They have been purchased over years so I don't remember amounts. They have been filled with distilled water primarily aside from 3 times with tap. (1) of the lbs were purchased a month ago to see if they had any effect. They had none.
-Johnson Controls temp controller. Setpoint of 71 degrees with a 5 degree drop. Thermocouple on unit is accurate within 2 degrees calibrated with alcohol thermometer.
-Hygrometer is dead on calibrated with a Boveda pack. I just ordered two more hygrometers though so I can get a better picture of the humidity distribution.

Performance:
Unit off, fan off:
Humidity stays at 65%

Unit off, fan on:
Won't be able to test until winter. The fan adds heat to the unit and it gets to uncomfortable regions within a day.

Unit on, fan on 24/7:
Temp hits 71, unit kicks on, temp drops to 66, unit shuts off, temp continues to drop to 65, temp increases to 71. Repeat.
Humidity drops when compressor is on then rises within a minute back to original value or slightly more. With each cycle the humidity raises a little further. The highest I let it go is 73% until I stop it.

Unit on, fan running only when compressor is on:
Temp hits 71, unit kicks on, temp drops to 66, unit shuts off, temp continues to drop to 61, temp increases to 71. Repeat.
Humidity drops when compressor is on then rises within a couple minutes back to original value or slightly higher. The humidity does not rise to 70+% as quickly without the fan running all of the time.

Unit on, fan off:
Similar to the last situation but I have concerns of no airflow

Next test:
Unit on, fan running with compressor, no beads:
I am going to run it for a day or two without any beads in it and see what happens right now. I will report back on 8/23.

My thoughts:
When I built this I knew water would condense on the back but I assumed that if X grams of water condensed on the coils then I immediately evaporated the water off of the coils it would result in a net change of 0 grams in the airs and the relative humidity would end up back at where it was. What I think is happening is that the beads put off moisture quicker then they will take it back in. So when the humidity drops the beads give off water, then the water is evaporated off of the coils leaving more moisture in the air. The beads have a harder time taking that moisture back in so they don't have enough time to drop the humidity down before the cycle starts again.

Possible solutions:
-Adding kitty litter which might suck up humidity quicker than the beads balancing the system.
-I tried adding a spanish cedar panel in the back of the unit to dampen the temperature gradient seen by the air. Humidity was solid at 65% if I kept a distilled water container in the unit. The wood was constantly wet though and I had a concern of mold growing. Also water was lost through condensation and went out the drain. I am contemplating cutting the bottom of the spanish cedar and sticking some beads under it to recapture the water. Then add a few more fans to maybe keep the wood dry. I don't think it will work though.
-I have no other ideas.

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You're misunderstanding relative humidity. If you take x grams of water out as the temperature drops and then reevaporate all the water at the lower temperature, the RH will be higher since you're closer to the dewpoint temperature. You need to remove the moisture from the space or store it in beads. You are probably reevaporating the liquid water faster than the beads can absorb it.
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Okay but once the temperature reaches the high temp again the relative humidity would again be at the same, it is higher so humidity is coming from somewhere.
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agreed
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Rh will always swing as the compressor operates. The only thing that is important is the Rh of your cigars. Put one hygrometer in one of your boxes and after 24hours check the high and low. It should be in an acceptable range. Beads will not immediately absorb or release moisture, but over the long run they will regulate within a range that should be acceptable. :-)

Dont worry so much about swings in Rh but more long term. Also, if your cigars are smoking fine there should be nothing to worry about. :-)
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Well the problem is that they aren't smoking very well, they are smoking like they are over humidified. I think I may have put way too much water on the beads in the beginning of the summer and I haven't been able to remove any due to a crazy hot and humid summer.
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Take your beads out, dry them out a bit with a hair dryer and throw them back in
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