Where the Moisture Comes From
Frost is just moisture that has found its way onto a cold surface and frozen. In a healthy freezer, the automatic defrost cycle melts the thin layer that forms on the evaporator and sends the water down a drain. Frost becomes a problem when either more moisture is getting in than normal, or the defrost cycle is not clearing it.
The most common everyday cause is a door gasket that no longer seals, often because it is dirty, tired, or the door is being blocked open by an overfilled shelf. Warm, humid room air pours in, hits the cold coil, and frosts.
Defrost Faults and What to Check
If the seal is good and frost still builds, the defrost system is the next place to look. A failed defrost heater, a defrost thermostat that will not close, or a control fault leaves the evaporator to ice over until airflow is choked and the freezer starts to warm. On the drain side, a blocked defrost drain can send melt water back onto the coil where it refreezes.
We diagnose by reading where and how the frost forms, then testing the gasket, the defrost components, and the drain to isolate the cause rather than just scraping the ice, which returns if the underlying fault remains.
Symptom Reference
| Symptom | Likely Cause | What We Do |
|---|---|---|
| Frost near the door | Door gasket not sealing | Clean or replace the gasket |
| Ice on the back wall | Defrost heater or thermostat | Replace the defrost component |
| Water refreezing at base | Blocked defrost drain | Clear the drain line |
| Frost plus warming | Airflow choked by ice | Diagnose defrost, clear coil |
Do Not Just Scrape and Move On
Clearing the frost without finding the cause means it comes back. A recurring frost problem points to a seal, defrost, or drain fault that should be diagnosed.
Book a Repair with a Specialist
Diagnostic and travel fees, if applicable, are confirmed before the appointment and before repair approval.