It sounds as if this may have electronic
controls on it. If so, the problem could be related to too low of an ambient temperature or too low humidity in the air. If this design has a temperature sensor built into it, you may be experiencing "hibernation mode", where the unit will appear to be dead, when it is actually awaiting the proper temperature to employ itself.
The following statement is a parameter for all dehumidifiers and some of the control issues may vary, but the theory is the same.
Most dehumidifiers have a "Frost Guard" mounted on the condensor coil. If frost accumulates on the condensor coil the frost guard turns the compressor off until the frost melts, then comes back on again. For the dehumidifier to work properly, the surrounding (ambient), temperature must be higher than 65 degress. This temperature allows the moisture in the air to condense on the coils and drip into the reservoir without freezing up on the condensor coil. Also, if the humidity is too low, (below 45%), the same condition will occur. So it will help to keep the parameters in mind when you have this issue.
Thank you for your allowing me to advise you on this issue.
Dave E. (Illeagle)