Unit appears to operate normally, but does not produce water

well 67%rh is considered low (70%rh is normal) units will produce much less water when tasked to operate in low moisture air , this is why all the new units have air temp ratings of 60Deg or less. but still the unit should try to go thru all the motions ,that you can easy verify , just by u watching /listening closely
set unit to work normally , listen 4 the fans inside to come on and a few moments later the compressor will come on if everything is working well , try adjusting the humidistat up to a value of say 80% listen 4 one fan and compressor to stop , this is all normal reset desired setting on humidistat
if unit fails any one of these simple tests it has an internal fault inside it and requires service

with a reading of 66 to 67 % rh this is a bit low for normal rooms humidity , I cant see why you'd want to try to get it down to 55% unless its for a special purpose (drying paint?) , I get this question a lot from folks , what I tell em is if you set your airconditioner in your home down to 30 degrees would your house ever get that cold = "no " the houses ability to heat itself is greater than the a/c units ability to cool it (even if its properly sized) so why would you expect a small appliance like a dehumidifier to be able to do any different ? all you end up doing is over working the appliance and costing you extra money in lost power
the general excepted room humidity is 70% rh this is a industry standard ,that all appliances are designed to achieve , and yes as the room gets dryer it will extract less and less water from air

when ice forms on an evaporator unit (coil) there is an indication of internal problems with the unit. IT may occur if there is insufficient air flow ( dirty or fan speed to low ) but when this happens the thermostat just orders more gas through the tx valve and so more ice is formed then the thermostat reads it as too cold and so cuts the gas flow back by controlling the operation of the tx valve
Water from a dehumidifier will depend on the atmosphere humidity so the lower the humidity reading the less water collected
However I suggest that you have a technician check it out as the compressor start/run capacitor may be faulty and that is why the compressor is not getting hot as it may not be running properly

There are 5 basic, but solvable reason for what you described. Please pay particular attention to numbers 1 & 2 .

1. The humidity extraction level is set to HIGH. Lower it to 32-35%.

2. Air intake filter is dirty or clogged. Turn unit OFF, & Unplug the
Unit, before removing to inspect & clean it, if necessary. If washed,
allow filter to completely dry before reinstalling. DO NOT operate
the unit without the filter.

3. Obstructed air flow. Maintain a minimum of 12 to 18" of clear air
space around the entire unit.

4. Cooling coils are dirty and need to be cleaned. Use warm water & dish washing liquid to clean
the coils. Rinse and wipe dry. Apply a light coating of WD40 to the coils.

5. Ambient air temperature at floor level is between 40 - 60 degrees.
dehumidifiers do not work well between those temperatures
(Unless, you have a Low Temp Unit). This applies mainly to
where the air temperature at floor level is colder than at shoulder
in basement applications level. Raising the unit up off the floor,
onto a sturdy table, counter top, etc, that can handle the weight
of the unit, plus a full tank of water, will usually resolve this
problem.

If none of the above solves the problem, it may be a case of the compressor needs to be recharged with refrigerant gas or that the humidity condenser sensor has failed. These things usually occur in units that are 5 years old or older. It's rare in a unit younger than that. But, it can happen.

Hope this helped you to troubleshoot and solve the problem.

You should check if the compressor is running. Your description makes it appear that the fan may be running and the compressor may not be running.

There are many things that can cause a compressor to cease running:

Open defrost thermostat
Bad run capacitor
Low refrigerant charge (caused by refrigerant leak)
Bad compressor relay
Bad compressor overload
Bad compressor motor

Other things to check:

If the fan switch is set to "on" and the humidity control is set to a high humidity level, the unit may appear to be running, but the compressor will not operate. Check the setting of your humidity control.

If the dehumidifier is operating in a room with a high temperature and a low dew point (very low relative humidity), it may be unable to remove any more moisture from the air.

If you are not comfortable troubleshooting the unit on your own, call the manufacturer service department at 1-800-533-7533, EXT 8459. They are very helpful.

Most dehumidifiers have a defrost mode in which the compressor is turned off to give time for the frozen water to melt. The freezing problem ocurrs when the unit is used in very cold weather. Check your manual to see if this unit comes with automatic defrost mode. If it does, it would appear that it is not operating correctly and you can request warranty service. If no defrost mode is available, then your only option is to heat up the room in order to use the dehumidifer within its limit of operation. Some units can operate as low as 36 F, but most units cannot go that low. Find out what your unit's specs are from the manufacturers web site.

I HAVE HAD A COUPLE OF UNITS THAT HAVE KEPT THE FAN RUNNING ALL THE TIME. I REPLACED THE CONTROL AND THAT TOOK CARE OF THE PROBLEM.

possible that the cooling fins have frosted over...this happens when a cold surface appears in a humid room that does not have enough heat to prevent the freeze-up on the fins. If you look at the fins (above the water bucket), you may see the frost. One solution is to turn up heat in room, followed by placing a fan to blow air through fins if still frosted. If you do not have a frost problem, then ensure compressor is running. If comp is running, then return dead unit.