The lower zone would not hold while the upper one stayed exactly right. The second fan had failed, so that zone was surviving on whatever drifted down. Both read true once the part came in.
Ignacio R.2026-02-20
wine storage
Sub-Zero wine storage temperature drift in Jacksonville
Stability matters more than the setpoint. What causes a zone to swing, and how we prove it over a full cycle.
Symptoms this sheet covers
- The two zones no longer hold different temperatures
- Corks pushing up, or seepage at the capsule
- Condensation forming on the inside of the glass door
- The unit runs far longer in the afternoon than at night
- A zone reads correct on the display but the bottles feel warm
General note 1 — scope of work
- On the ticket
- Built-in and integrated Sub-Zero refrigeration, indoors, in a kitchen or a pantry: refrigerators, freezer and refrigerator columns, undercounter cabinets, wine storage and ice machines. The sealed system, the controls, the fans and defrost, the door and its gasket, and the opening the cabinet is trimmed into.
- Not on the ticket
- Heating and air conditioning. We do not install, service or diagnose furnaces, heat pumps, air handlers, condensing units for the house, thermostats for the house, or ductwork. We are not an HVAC contractor and not a ventilation contractor, and we do not hold ourselves out as either.
Wine storage is the one cabinet in the house where stability matters more than the number on the display. A unit holding two degrees warm and holding it steadily is doing its job. A unit that swings several degrees between afternoon and midnight is pumping the air in and out of the cork on every cycle, and that is the mechanism behind pushed corks and seepage at the capsule.
So the first thing we do is not adjust anything. We log.
A day of data before a diagnosis
We place independent probes in both zones and record for a full cycle, ideally across an afternoon and an overnight. What we are looking for is the shape of the curve, not the average:
- A slow steady sawtooth within a degree or so is normal compressor cycling.
- A wide swing that tracks the room points outward — solar gain through the glass door, a nearby appliance, or a cabinet run with no ventilation.
- A step change at a fixed time of day usually means something else in the house is loading the circuit or the room.
- A drift in one zone only isolates the fault to that zone’s damper, sensor or fan rather than to the sealed system.
That distinction saves money. A zone problem is a component. A whole-cabinet problem may not be the cabinet at all.
What we check inside
Both zone sensors against a calibrated probe. A sensor that has drifted will hold the compartment at the wrong temperature while displaying the right one. This is the single most common cause of “the display says 55 but the bottles are warm”.
The damper or zone divider. In a dual-zone cabinet the zones are separated by an air management arrangement, and a damper that no longer closes fully lets the two zones equalise. The symptom is exactly the one homeowners describe as “the zones stopped working”.
Evaporator fan and airflow behind the racks. A wine cabinet moves very little air by design. Blocking it with a full rack pushed hard against the back wall is enough to create a warm shelf at the top.
Door seal and glass. A glass door is a large cold surface in a humid room. Interior condensation is normally an infiltration problem at the seal, not a failure of the glass.
Installation clearance. Undercounter and built-in wine units reject heat through a grille that is frequently boxed in during a kitchen remodel. If the exhaust has nowhere to go, the cabinet cannot hold a low setpoint on a hot day no matter what is set.
The Jacksonville variable
Room temperature is the load. A butler’s pantry on a west wall in a Jacksonville summer can sit ten degrees above the rest of the house through the afternoon, and a wine cabinet sized for a conditioned interior will run continuously trying to keep up. We record the room as well as the cabinet, because half the “unit too weak” complaints we see resolve when the room is dealt with.
Humidity is the second variable. A cabinet in an unconditioned garage or a screened room will sweat regardless of the seal, and no repair changes that.
What you get
A written record of both zones over the logging period, the measured sensor error if there is one, and an estimate before any part is ordered. The flat diagnostic fee is credited toward the repair.
We are independent, we do not act for the manufacturer, and we service Sub-Zero refrigeration only. Parts are genuine OEM, carrying 365 days of parts coverage and 90 days on labor.
What does wine storage temperature drift cost to put right?
One number is known before the van moves: $80 to read the cabinet, credited against the work if you approve it. Everything scheduled beneath it is a band and not a figure, because the part sets the number and the part is not named until the readings are in.
| Item | Band |
|---|---|
| Reading the cabinet, diagnostic sequence | $80 flat |
| Door gasket or seal replacement | $230–$620 |
| Evaporator or condenser fan motor | $270–$580 |
| Defrost heater, thermostat or sensor | $240–$640 |
| Ice maker, water valve or supply line | $250–$670 |
$80 buys the readings; $670 is the ceiling of everything scheduled above it. The written estimate sits between the two and carries one figure, handed over before a part is ordered.
Asked and answered
Questions that come up on wine storage temperature drift
- Is a zone set two degrees warm worse than one that swings?
- The swing is worse. A cabinet holding two degrees warm and holding it steadily is doing its job. One that moves several degrees between afternoon and midnight works the air in and out of the cork on every cycle, which is why both zones are logged over a full cycle instead of read once.
- Why does it run so much harder in the afternoon?
- Because it is working against the room. A glass door, a west-facing wall, a neighbouring appliance or a cabinet run with no air moving through it all raise what the unit has to reject. Where the load is the room rather than the machine, the estimate says so and nothing is replaced.
- What does wine storage work cost?
- $80 flat to diagnose. Where a fan motor is the cause, the work runs $270–$580; where a defrost part or a sensor reading low is the cause, it runs $240–$640. Logging both zones over a full cycle is part of the diagnostic, not an extra line.
Book the diagnostic
Flat diagnostic fee, credited in full toward the repair if you approve the work. Written estimate before any part is ordered or any labor is billed. See the pricing sheet for how the fee works and the warranty sheet for what the finished repair carries.
Call +1 (904) 977-8701Customer feedback
What owners said after wine storage temperature drift work
4.5 out of 5 across 71 customer reviews. Read every one of them.
Condensation on the inside of the glass every afternoon without fail. He measured the room as well as the cabinet, and was straight with me that the west wall was half of the problem.
Ambrose W.2026-03-02
The wine cabinet had drifted several degrees and the upper bottles were noticeably warm. He cleaned a badly loaded coil, then confirmed the result against a probe rather than trusting the front readout.
Seraphina T.2026-07-26