subzero 501R and 501F

[JoanManning]

I have a subzero refrigerator (501R) and freezer (501F) purchased new in 1995. The back panel of both are frosting and the freezer is the worst. Freezer has had this problem for a number of years. Refrigerator is a recent event. What could  be causing this? Is this something we can fix or should we contact a repair per :thanks:son.

Thanks

Joan

[tgoods]

The freezer probably has a defrost problem.  The defrost system has three components; timer, heater and thermostat.  Advance the timer until it clicks into defrost mode.  If the heater comes on, replace the timer. If not, check the defrost thermostat and heater with a meter to determine which one is bad.

The refrigerator probably has a leaking evaporator.  This requires special tools and training and is beyond what a typical DIY'er can do.