Model Number:
Brand: Brand
Age: Less than 1 year

Model Number: MFU14M2GW4
Brand: Frigidaire
Age: More than 10 years

Hello, all!
I have a the following upright freezer:
-- Brand: Frigidaire
-- Model: MFU14M2GW4
-- Age: ~12 - 15 years
This morning my wife found that there was a lot of built up ice crystals in the freezer - kind of like the door hadn't been closed all the way. And, the food really isn't frozen anymore.

When running normally, the freezer makes a decompressing, suction-like sound when you close the door. However, it's not doing that now. Also, the sides and top of the freezer are quite warm. When plugged in, it doesn't make any noise.

Any ideas on how to troubleshoot this would be greatly appreciated.

Thanks!
-Adam