Coils Ice Up and nothing is dehumidified

If the coil is clean, then have a tech check for a low charge. This will cause the coil to freeze up. Humidifers are known to lose gas and owners aren't told this so end up buying new one and scraping the old one. Trust me on this. I have seen this many times. I repair high end machinery as my business.

Problem: Coil frosts up and prevents air flow. Then a solid mass of ice forms and finally drips into the pan - but power consumption goes out of sight.
Air must flow to achieve results. Possible simple "home made" solution.
Send air from outflow side back to inlet side to increase temperature at inlet with partially dehumidified air. Make an "ear ****" of pipe that you place over the machine by resting it on the top. It will take (4) pipe elbows and a short straight piece at the top to do this. You could also do this with an aluminum expandable metal dryer vent hose if you can figure out how to hold it in position. I would start with 4 inch. gas hot water heater vent pipe elbows and probably about 16 inch length of straight pipe. Put the "****" on the dehumidifier until the humidity gets below the irritating frost level.
Then remove the "****" to achieve maximum performance. (Note: the area around the "****" will frost up and all the air will go through the coil just behind the pipe. When the coil starts to melt out from the center portion, then you are almost ready to remove the "****") Leave the filter off until you reach the no frost condition.

Im no expert but obviously a dehumidifier works by cooling the air to condence it from a gas (vapour) to a liquid. For some reason yours is cooling it even more and turning the vapour into a solid (ice). Therefore it must be cooling it too quickly, the only thing I can think of would be to turn the temp up somehow. Is there a dial you can adjust (humidistat)?