In No-Frost models, heater melts ice every 6-8 hours. If ice builds up, heater is dead or bi-metal sensor failed. Fix before ice fully blocks airflow.
See if any of these signs match your device — each one increases the likelihood of this fault.
These are the causes we encounter while repairing Ice buildup on freezer walls — ranked from most to least common.
Burnt defrost heater
Failed bi-metal sensor
Faulty defrost timer (old models)
Worn freezer door gasket
Frequent door opening = humidity
PCB defrost circuit fault
Any of the following = a danger signal — call now and don't try to fix it yourself.
On-site diagnosis, clear pricing before any work, and a documented 6-month warranty.