When a Sub-Zero refrigerator section is warm but the freezer is cold, the cause is usually specific to the fresh food system: a failed fresh food evaporator fan, an iced evaporator from a defrost failure, a faulty fresh food thermistor, or a refrigerant valve or damper that isn't switching on single-compressor dual-evaporator models.
Sub-Zero's dual refrigeration keeps fresh food and freezer cooling separate. That's great for food quality, and it's also why one section can fail while the other keeps working.
Check These First (5 Minutes, No Tools)
- Listen inside the fresh food section for the fan when the unit is running (press the door switch if needed).
- Look for frost on the rear panel of the fresh food section.
- Move items blocking the rear air vents.
- Check the fresh food set point.
Most Common Causes
| Cause | What happens | Fix |
|---|---|---|
| Fresh food evaporator fan | Fan stops; the coil stays cold but air doesn't move. | Pro |
| Defrost heater / sensor | Fresh food evaporator ices over and blocks airflow. | Pro |
| Fresh food thermistor | Control thinks it's colder than it is. | Pro |
| Refrigerant valve or damper | Cooling never gets directed to the fresh food side. | Pro |
| Control board | Output to the fresh food fan or valve fails. | Pro |
How We Fix It
We test the fresh food fan, defrost heater, sensors and valve or damper operation, and read stored faults. These parts are usually in stock, so we finish most of these repairs the same visit.
When to Call a Technician
If the basic checks above don't solve it within a few hours, or if you hear repeated clicking, see an alarm or service indicator, or notice water under cabinetry, call us at (725) 237-7399. The $75 service call is credited toward your repair, repairs carry a 1-year parts and 180-day labor warranty, and we stock the Sub-Zero parts behind most of these failures.
Typical Cost
| Repair | Typical range |
|---|---|
| Evaporator fan motor replacement | $345 – $595 |
| Defrost heater / defrost sensor repair | $395 – $745 |
| Thermistor (temperature sensor) replacement | $265 – $445 |
| Control / user interface board replacement | $595 – $1,250 |
Typical totals for parts and labor in the Las Vegas area. The $75 service call is credited toward your repair, and every repair is backed by a 1-year parts and 180-day labor warranty. Your exact price depends on the model, the part and access, and you approve a firm quote before any work begins. Full price list →
Still Not Working? We Can Help Today.
$75 service call, credited toward your repair · 1-year parts · 180-day labor warranty · EPA 608 certified · Mon–Fri 8am–7pm · Sat–Sun 8am–4pm