It depends on the size of the room, the ambient humidity, and your target humidity. For example when I run my dehumidifier in the bathroom it cycles every few minutes because it doesn't take long to get the space to the target humidity, but when I run it in the living room it may take 15-20 minutes to reach target humidity before it cycles to fan mode. It's relatively dry where I am so once it dehumidifies the living room, it might be another 10-15 minutes before the compressor kicks in again.

You didn't say where you're located but if it's very humid there, it won't be long before moist air seeps back into the space so this could account for why you're seeing it cycle so fast.

It sounds like the 'differential' on the humidistat is too 'tight'. Another words it's too sensitive. There might be a set screw to adjust it.

I'm sorry I overlooked your all responses. After some research I decided the problem might have to do with the fact the humidistat sensor is inside the unit's case and thus is exposed to excess humidity from all the water in the humidifier's bucket. (This is an observation made by someone else--I forget who and where.) I called Hisense tech support and asked the representative if that might be the case and he called the suggestion 'astute,' which I took to mean 'yes, indeed.'

I returned the Hisense and bought a Whynter, which does the same thing. It is, however, a little better looking, in my opinion, and maybe a bit quieter. I've taken to letting it run continuously until the bucket fills and it turns itself off. This is taking about 6-8 hours. I empty the bucket twice daily, which I don't find onerous, and the humidity stays in a reasonable range.

Geoffrey, your suggestion sounds like it might work. If I can find out how to make that adjustment (the term, 'dead band' comes to mind) I'll give it a try.

The issue is the humidity sensor is placed too close to the condenser coil. when the fan turns off the humidity begins to evaporate off that coil and the sensor detects a increase in humidity. The way to solve this is to have the fan running continuously so it always pulls the humidity out of the coil chamber so it doesn’t flow out the back of the unit. Sadly this is a problem all dehumidifiers have, and you need to get one with a continuous running fan for it to not have the issue.

There IS insufficient "dead band," so that when the humidity is near the set point the compressor runs only a short time. Our new 50-pt Frigidaire does it. So reset to "C" and add a 24-hr timer to switch the mains on and off for hours at a time. (Setting retained while mains are down.) Far fewer on-off compressor cycles and thermal cycles of all the piping. Maybe the machine won't spring a freon leak and fail so soon. BTW, use a killawatt to detect failure. When the power drops from 500~550w to 350, the compressor is unloaded because the refrigerant is gone and the dehumidifier is shot. Comments welcome.