I don't know whether this is the only problem in my refrigerator, but it's the one I know about. My defrost heater has burned out at one of the connection points where the wire attaches to the element. It doesn't seem to have harmed the coil but the wall is charred where it happened.

It is, of course, not possible to obtain a direct replacement, so I need a reasonable substitute. I thought I might have found one in the Whirlpool 978332 heater assembly but it is also discontinued. I need advice for finding a substitute.

I'm not interested in replacing an otherwise working refrigerator just because it's old. Any advice would be greatly appreciated!