Refrigerator·Moderate·45–90 minutes·DIY $0–$150·Pro $150–$900
If the coils are clean, both fans run, the defrost circuit tests good and the compressor runs continuously without the evaporator ever getting cold, you are looking at the sealed system — a low refrigerant charge, a restriction in the capillary tube, or a compressor that has lost compression. Telltale signs are a suction line that never gets cold to the touch, frost on only the first few inches of the evaporator, or an oily residue around a weld joint. Opening that system legally requires EPA Section 608 certification and recovery equipment, so it is not a DIY repair. Expect $400–$900, and get that quote before committing on a unit over ten years old.
Freezer·Moderate·45–90 minutes plus a 24-hour defrost·DIY $15–$150·Pro $150–$450
If the heater, thermostat and drain all check out and the coil still ices over, the control board is not commanding a defrost cycle, and that is a board diagnosis worth paying for rather than guessing at. Call a professional immediately, and do not run the unit, if you find an oily residue anywhere on the evaporator or the tubing — that indicates a refrigerant leak, and sealed-system repair legally requires EPA Section 608 certification. On a chest or upright freezer over ten years old, get the sealed-system quote before assuming repair is the right call.
Ice Maker·Moderate·30–90 minutes plus a 24-hour wait·DIY $25–$220·Pro $150–$400
If the module fails its test cycle, replacing an ice maker assembly is a $90 to $220 part and is a moderate DIY job on most models — two screws and a wiring harness. Call a technician if the freezer cannot hold 5°F, since that is a refrigeration fault and possibly a sealed-system one requiring EPA Section 608 certification, or if the fault turns out to be in the main control board rather than the ice maker itself. Low household water pressure is a plumber's problem, not an appliance one.
Wine Cooler·Moderate·30–75 minutes·DIY $0–$120·Pro $150–$600
On a compressor wine cooler, if the coils are clean, the fans run, the seal is good and the compressor runs continuously without cooling, the fault is in the sealed system — and that work requires EPA Section 608 certification. Get the quote before authorising it: sealed-system repair often runs $300 to $600 against a replacement cooler at $200 to $800 for typical undercounter sizes, so the maths frequently favours replacement. Control board faults on either type should be confirmed by measurement rather than bought on a guess.
Refrigerator·Moderate·30–90 minutes·DIY $0–$80·Pro $150–$400
If the leak is coming from the sealed system — an oily residue around a weld joint, or frost forming on the suction line — stop. That is refrigerant, and repairing it requires EPA Section 608 certification and recovery equipment. Likewise, if you have cleared the drain twice and it keeps freezing solid, the defrost heater or defrost thermostat is failing and the whole defrost circuit needs testing.
Freezer·Moderate·45–90 minutes·DIY $0–$150·Pro $150–$900
If the coils are clean, both fans run, the seal is good, the relay is fine and the compressor runs continuously without the cabinet getting cold, the fault is in the sealed system — low refrigerant, a restriction, or a failing compressor. That work legally requires EPA Section 608 certification and typically costs $400 to $900. Weigh that carefully: a new chest freezer starts around $250 and a new upright around $500, so on a unit over eight years old, replacement is very often the better call. Get a written quote before authorising sealed-system work.
Ice Maker·Easy·20–45 minutes plus a 24-hour wait·DIY $25–$90·Pro $150–$350
If flow at the dispenser is strong, the filter is fresh, the fill tube is clear and the freezer holds 0°F but the cubes are still undersized, the inlet valve is not opening fully or the ice maker's fill timing has drifted, and both are worth a technician's measurement before you buy parts. If the freezer cannot reach 0°F, that is a refrigeration fault first — and any sealed-system work requires EPA Section 608 certification. Low household water pressure is a plumbing issue rather than an appliance one.
Wine Cooler·Moderate·30–75 minutes plus a 48-hour log·DIY $0–$70·Pro $150–$400
If the sensor checks out against the chart, the load and seal are right and the cabinet still swings widely, the control board is misreading or its relay is chattering, and that is a board-level diagnosis worth paying for rather than guessing at — boards for smaller wine cooler brands are frequently unavailable, which is itself worth knowing before you spend anything. On a compressor model that runs continuously without holding setpoint, the fault is in the sealed system and that work legally requires EPA Section 608 certification.
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