Regarding drying peppers in a food dehydrator, I would recommend against it. Even at low temperatures, most dehydrators will exceed 100 F. degrees, which can weaken or destroy most seeds. Before making such an attempt, you could place a thermometer in the dehydrator at the lowest setting, to verify its actual temperature. And if the temperature
was low enough to safely dry seed, that would probably not be low enough heat to dry the whole peppers before some of then spoiled.
Likewise, if you store peppers in the fridge, they - and their seeds - would almost certainly spoil before Spring. The longest I've been able to store peppers in the fridge is December, about 3 months after harvest. A few hot pepper varieties might last longer than that, but IMO its not worth the gamble.
The great thing about peppers is that you can remove seeds for saving as
@so lucky mentioned, and still eat or dehydrate the pepper itself. This is fairly easy for most varieties, with a couple precautions.
Be sure to use good, high-mil rubber gloves when opening hot peppers, such you will find in a hardware store. The thin dollar-store varieties will
not provide enough protection. If the peppers are still juicy, the chemical which causes peppers to taste hot (capsaicin) will penetrate the gloves, and your hands (and any part of your body you touch afterward) will feel the burn. I & several of my friends all learned that lesson the hard way, we all laugh about it & share horror stories.
Also, be aware that when wet, hot peppers can give off fumes. If you have respiratory issues, or just don't like coughing & sneezing, clean peppers in a place with good ventilation. Temperatures permitting, outdoors is best; but I also clean (or powder) hot peppers under the stove exhaust hood... provided the vent exhausts outside, that works well.
Once the seeds are removed, dry them on newsprint or other clean paper. Once dry, any clinging flesh which may be attached to the seed, will usually remain on the paper when the seeds are removed. For some thin-walled hot peppers (such as a Thai pepper I grew this year) I remove the stem & cut them in half lengthwise to dry, seeds and all. This is best done under a fan, or in an area with good air flow - such as a garage. The seeds can easily be removed once the peppers have dried.
Pepper seeds are dry enough for storage when they break in half under pressure, rather than bend. Like
@digitS' , I leave the seeds out until the ambient humidity has lowered - which naturally occurs here in early Winter, when the forced-air heat is running. When the sweater starts sparking, the humidity is low enough, and the seeds can be stored in jars, freezer bags, or other air-tight containers.
This process is not really as hard as it sounds; peppers are actually one of the easiest seeds to save, once the basic precautions have been taken.