I used a dehumidifier in my extraction room, I found it helped keep the room warm as well as dry. I figure if you need to heat your extraction room you may had well heat it with a dehumidifier as they are all most as efficient as heating as heaters anyway.
If you want to dry your frames after uncapping but before extracting then I would do as the video above, just leave them in the supers and stick a fan above. The air moving over the frames will help evaporate the moisture. If you can some how get the dry air port from the dehumidifier to blow over the frames that would be even better.
On a good dry summer day <=40HR, you honestly wont even need to use a dehumidifier, so long as you have a fan and good ventilation. I dried a bucked of honey with a fan and a electric drill set up to stir. So am sure just the fan will work on uncapped frames in the right weather.
There are 2 common types of dehumidifier tech. Compressor or desiccant. Compressor works best at 20c and costs less to run. Desiccant ones use more power, put out a lot more heat, are generally less efficient (except at extreme temps), but will work over a wider range. If you intend to put honey in a confined space to dry, I recommenced Compressor or it will get too hot. But to heat a large honey room in place of heaters, look at the desiccant ones. Some of the 12L Desiccant ones can consume 600W, and that basically all ends up as heat in the end anyway.