Is it possible to buy a portable dehumidifier which will automatically restart and function after a temporary power outage? What do you ask for?

Hello William, thank you for your post!
I understand that you would like to have a dehumidifier that restarts after a power outage. I have reviewed the available models for Frigidaire and show that feature is not available. You may want to speak with additional manufacturers for that feature. I hope this information is helpful to you. -Matt

Any working dehumidifier should restart after an outage if the humidity is high enough relative to the setting.

So check that your current unit functions properly by varying the setting and checking that it comes on. If not, that is the problem and will be solved by a new unit (or repair to current one).

If it passes that test, put it on a timer that turns it on and off a few times a day and check that it works properly after each restart. That is the same as a power failure as far as the unit is concerned. If not, a new unit is called for.

Subject the new unit to these 2 tests. If it passes you are good to go away. If not, return within refund period.

I wouldn't buy from any retailer that didn't know that this is not a feature that would be listed, but is AUTOMATIC with ALL models.

Consider having 2 units set some distance apart in your house/apartment. Each will work less and more efficiently, and could serve as the backup if the other fails. $100 is a small insurance policy against mold.