Symptoms

Uneven coil frosting 

Possible Causes ‍

1. Defective heater
2. Located close to the door or opening vents
3. Defrost termination set too low
4. Incorrect or missing distributor nozzle

Possible Corrective Steps 

1. Replace heater
2. Relocate evaporator
3. Adjust defrost termination setting higher
4. Add or replace nozzle with appropriately sized orifice for conditions

‍