Is there a way to dehydrate food without using a dehydrater?

This web site lists various methods for drying foods.

I think TVC have some Catering Equipment for this kind of food service, well I know they sell bradley smokers which can dry foods but I'm not sure on what other catering equipment they have that might do this kind of job so you will have to take a look.

Yes, you can use your oven ... I've done it many times with constant success. 

Marinate your meat, if you're using meat, in a marinate or brine of your choice, for example a combination of soy sauce & brown sugar ..... overnight in the fridge. Then set your oven to the lowest temperature and prop the oven door slightly open for the moisture to escape. Drain and place your meat directly on the racks or on a rack over a baking pan. Cure it until you get the texture of your choice (8-12 hours). You can also use this same technique to dry fruits & veggies.

Hope this helps you out!

Can you make jerky in a regular home oven? Yes, a home oven can be used as a makeshift food dehydrator. Food dehydration essentially requires two basic elements; heat and air flow. These two elements work in concert to remove moisture from food. As the heat warms the food, its moisture is released and evaporated into the air. To dehydrate food in an oven, you simply place food items on the wire racks in your oven, set the heat and leave the oven door slightly ajar to let air and moisture out.  But a dehydrator is better due to its fan and air movement.

http://www.food-dehydrator.com/resource-center/how-to-make-jerky-in-an-oven.aspx

The maintanence of your refrigerator is very important to the over all long life of the appliance.  A routine check up and cleaning will go a long way in making sure your refrigerator runs for years to come. A tune up should take place on a yearly basis.  You can call your local repair man for details.