Sub-Zero Compressor Runs and Nothing Gets Cold
Compressor, condenser, evaporator and refrigerant faults — measured last, because five cheaper stages can each make a healthy circuit look sick.
A sealed system fails on heat load, on dust, on vibration and on age. It is the most expensive assembly in the cabinet and the least likely explanation for the symptom most people call about, which is why it is measured last — after supply and controls, after the condenser and its clearance, after the door, and after the cabinet has been logged against setpoint through a cycle. Each of those can make a perfectly healthy circuit measure badly.
Dual refrigeration means two of everything
Sub-Zero built-ins and paired columns run separate refrigeration circuits for the fresh food and freezer compartments — an advantage in normal use and in diagnosis. A freezer holding at setpoint while the fresh food side climbs is not a mystery: it says which of the two circuits to look at. It also means an estimate for one system is not an estimate for the cabinet.
The corollary trips people up. Two independent circuits rarely fail together, so if both compartments are warm at once, suspect something they share — power, control, a condenser choked for both — before two sealed-system faults.
Condenser restriction comes first, and it comes here early
Before anything is opened, the condenser gets read. Built-ins here run their condensers against high ambient heat for eight months of the year, and a coil packed with dust and pet hair adds head pressure to a system already working. A restricted condenser produces the exact symptom list owners describe as “the compressor is going”: long runs, poor recovery, warm cabinet, more noise.
It is also the one item here an owner can influence: a condenser cleaned on a schedule buys years on a compressor. We will show you the grille and the interval that suits your kitchen rather than sell you a subscription.
Evaporator, defrost and the difference between them
Frost on one section of an evaporator with clear metal on the rest is a refrigerant-charge or restriction pattern, not a defrost fault. Uniform heavy frost, in a cabinet that recovers after being emptied and left open, is usually defrost — a heater, a sensor or a control that has stopped running the cycle. They need different parts and different money, and the only way to tell them apart is to measure rather than look.
Refrigerant work is regulated
Opening, recovering from and recharging a refrigeration circuit requires EPA Section 608 certification under federal law. Our technicians hold it — the one certification claim on this site, and a genuine one. We are an independent repair company working on Sub-Zero refrigeration only.
Storms take boards, not compressors
Around 68 thunderstorm days a year pass over this part of north-east Florida, and what they damage is control electronics, not mechanical refrigeration. A cabinet that went dead during a July storm and shows no display is a different investigation from one slowly losing ground since spring. We do not treat them as the same call, and neither should any estimate you are handed.
A sealed system does not consume refrigerant
Worth stating plainly, because it is where owners are most often overcharged elsewhere. A sealed circuit is sealed: it does not use refrigerant up, so it does not need topping up, and anyone offering to add a little gas without finding the leak is describing bad practice — and, done in the open, an illegal one. If a circuit is low it has lost refrigerant somewhere, and the loss is the repair.
Is it worth replacing the compressor?
On a full-size built-in, usually — and it is arithmetic rather than a matter of opinion. The comparison is what the repair costs against what putting a comparable cabinet into the same opening costs, joinery included, and on this equipment those two figures are not close to each other. On a wine cabinet or an undercounter unit they are much closer, and there the question is a real one. Both sets of figures are published, with the division done in front of you, on worth repairing.
What decides it more often than the figure does is whether the component is still made and how long the wait is, which is why availability is checked before an estimate is written rather than after it.
Parts, serial numbers and lead times
Availability gets checked before a figure is written down, because a repair you cannot get parts for is not a repair. The serial number decides which revision of a component fits — two cabinets that look identical across a kitchen can take different parts — so we ask for the plate reading before the visit. Lead time goes in the estimate for the same reason: a part on a shelf and a part on a four-week backorder produce different decisions, and you should be making that decision with the date in front of you, not after the cabinet is apart.
Repair or replace, with the numbers written down
Built-in refrigeration is worth repairing far longer than a freestanding appliance: the cabinet is fitted to a specific opening — often on rails, usually behind joinery, sometimes behind a custom panel — and replacing it is cabinetry work as well as appliance work. That second half of the bill is rarely in the showroom price.
Which argues for repairing more often, not for repairing at any price. Nocatee’s housing stock starts in 2007, so the first phase of built-ins here is past the point where original sealed-system labor coverage typically ends, and that makes a sealed-system quote a genuine decision. The estimate gives you the repair cost, the parts availability and lead time, and an honest view of what the cabinet has left — in writing, before anything is opened.
The diagnostic is $80 flat, credited toward the repair if you go ahead. Completed work carries 90 days on labor and 365 days on parts, genuine OEM.
What does sealed systems work cost in Nocatee?
$80 flat to diagnose, credited toward the repair once you approve it. Completed work on this page has landed between $250 and $2,270, parts and labor together. The firm figure is written down after the diagnosis, not before it.
| Repair | Typical range |
|---|---|
| Diagnostic visit, credited toward the repair | $80 |
| Compressor or sealed-system repair | $910–$2,270 |
| Evaporator or condenser fan motor | $260–$570 |
| Defrost heater, thermostat or sensor | $250–$590 |
Ranges are what this work has cost, not a quote. A range moves with the part version the serial number calls for and with what the cabinet turns out to need. The whole table is on the pricing page.
How much does sealed systems work cost in Nocatee?
$80 flat to diagnose, credited toward the work. Completed repairs in this category have run $250 to $2,270, parts and labor together. The band your cabinet lands in is written into the estimate before anything is ordered.
Do you charge more for a harder-to-reach cabinet?
No. The $80 is the same whether the unit is a column behind flush panels, an undercounter drawer under a counter run or a wine cabinet in a butler pantry, and the same anywhere inside St. Johns County.
Do you work on anything other than this brand?
No. Sub-Zero refrigeration only, and that is a deliberate limit. One line of equipment means the parts on the van match the appliance in the opening and the service positions are already known. We turn other work down.
$80 flat to diagnose, credited toward the repair if you go ahead with the work. 90 days on labor, 365 days on parts. Pricing · Warranty · Contact
Calls about sealed systems, as owners described them
Three of the Sub-Zero owners who called us, picked because the call was about this equipment.
4.64.6 out of 5 — the mean of all 60 reviews collected after a visit
5 out of 5
Refrigerant work is the part I dreaded most and he treated it as the last resort it should be. Five other checks came first, all documented, and only then did the gauges come out of the van.
Colette A.June 2026
5 out of 5
The compressor was running almost without stopping and frost was creeping up one freezer wall. He checked the coil and the door before going anywhere near the sealed system, then confirmed a low charge, repaired it and recharged.
Whitney A.December 2025
5 out of 5
Two other outfits had already told us to replace the whole unit. He took pressures in front of me, walked me through the readings, and showed a slow leak at the evaporator rather than a dead compressor. Repaired once the part landed.
Terrence Q.October 2025