This 20 year old fridge works fine except that about six months ago it started making a loud buzzing noise, which lasts for about 15 seconds and repeats every 15 minutes. So, yes, it gets quite annoying.

Can this noise be stopped by installing a new part or by cleaning part of the fridge?
The coils that are partially accessible from the front and bottom of the fridge, for example, are fairly clean. It's hard to get in there to do a really good cleaning job, but at least the coils that are closest to the front of the fridge are clean.

While all fridges make noise as the motor runs, this noise is different.
It's almost like the noise a built-in ice maker might make, except that this fridge has no built-in ice maker.

I also appreciate that it may not be easy to get parts for a 20 year old fridge, but cleaning certain parts of the fridge may help as well.

Thanks for any tips.

I think it's one of two things:

1. One of the end bells on the evap fan motor is running dry, and may need oiling.

2. The compressor relay may be worn and in need of replacement.

Parts are still available for this older model, including the compressor, so I'll look into these possibilities.