Sub-Zero · Refrigerator error code

40 1 38Refrigerator stepper valve communication fault

Cross-checked Licensed pro only

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Stop: this involves gas or the sealed refrigerant system.

OnCall Tech only describes the symptom. Gas work needs a licensed gas technician, and refrigerant work requires EPA Section 608 certification. If you smell gas: shut off the supply if it is safe, do not switch anything on or off, ventilate, leave the building and call the gas utility.

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

Related diagnostic guides

Guide · Refrigerator

Water dispenser not working (ice maker may still work)

If ice is still being made, the water supply reaches the valve, so the fault is usually a frozen door line, the dispenser-side valve coil, the dispenser switch or a lock mode. Isolate the problem by section.

5 steps ~40 mineasy

Guide · Refrigerator

New or just-moved refrigerator not cold yet: normal pull-down time vs a real fault

A refrigerator started from room temperature needs hours to pull down and up to a day or more to settle, longer in a hot room or if it was loaded right away. Ice comes later still. Before treating it as a failure, confirm it is actually running (not in showroom/demo mode), the doors seal, it was not lying on its side, and give it the manufacturer's window.

6 steps ~20 mineasy

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