The seal work was done properly and the sweating stopped. What I did not like was being told a part was in stock when it was not, and finding that out on the day of the second visit.
Mortimer A.2025-11-19
door and gasket
Sub-Zero door seal and condensation in Jacksonville
Water on the frame, frost in one corner, or a door that drifts open — the seal is doing less than it looks.
Symptoms this sheet covers
- Water beading on the frame or the door face
- Frost building in one upper corner of the freezer
- The door swings back open unless it is pushed
- A visible gap along the hinge side near the top
- The gasket feels stiff, flattened or torn at a corner
- Produce spoiling faster than it used to
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.
A door seal is not a rubber strip. It is a magnetic gasket that has to make continuous contact around a full perimeter against a cabinet that is under slight negative pressure when it is cold. Break contact anywhere — even a sixteenth of an inch over four inches of run — and humid room air moves in continuously.
In Jacksonville that matters more than it does in a dry climate. Summer dew points here sit high enough that infiltrating air carries a great deal of water, and that water has to go somewhere. It goes onto the evaporator as frost, into the compartment as humidity, and onto the coldest exterior surface as condensation.
The three symptoms and what each one means
Sweating on the outside of the door or frame. Warm humid air is reaching a surface that is below its dew point. Usually the seal has lost contact, but on a built-in it can also mean a failed anti-condensation heater in the frame or an insulation void. We check the seal first because it is far more common.
Frost in one corner of the freezer. Frost is directional evidence. It builds where the moisture enters, so a frost patch in the upper hinge corner tells us where to look before we have touched the door.
The door drifting open. A built-in door is heavy, and the hinge carries a closing action. When a door will not hold shut, either the cabinet is out of level, the hinge has worn, or the door was rehung after a panel change and never re-adjusted.
How we test it
Level and plumb, both cabinet and door. We measure the cabinet in two axes and the door reveal at the top, middle and bottom. A reveal that varies more than a small amount from top to bottom means the door is not parallel to the frame, and no gasket will seal that.
Contact test around the full perimeter. A thin strip drawn out at intervals tells us where the grip is and where it is not. It is crude and it is decisive.
Gasket condition by hand. We look for compression set, a flattened crease where the door has been resting for years, a corner that has pulled out of its retainer, and hardening. A gasket that has gone stiff has lost the ability to follow a slightly imperfect frame.
Hinge and closer condition. Play at the pin, and whether the closing action still returns the door over the last inch.
Room conditions. We record kitchen temperature and humidity. If a cabinet is sweating in a kitchen sitting at 78 degrees with no ventilation running all summer, the appliance may be operating correctly and the room is the variable.
Why old kitchens fail this test more often
Houses in Riverside, Avondale, Old Ortega, San Marco and Old Mandarin sit on century-old framing over long joist spans. Heart pine moves with the seasons. A built-in that was set dead level at installation can rack by a small amount within a year or two, and the first sign is always condensation, never a door that visibly will not close.
The fix in those kitchens is often shimming and re-levelling rather than a new gasket. We would rather sell you the correct hour of work than a part that will be flattened out of shape again by the same floor.
What it costs
Gasket replacement is a genuine OEM part with 365 days of parts coverage. Levelling, hinge adjustment and door alignment are labor, quoted in writing after the measurements are taken. The flat diagnostic fee is credited toward the repair when you approve it.
We are an independent company servicing Sub-Zero refrigeration only.
What does door seal and condensation 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 |
$80 buys the readings; $620 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 door seal and condensation
- Is water on the door a fault, or just a humid kitchen?
- Both are possible and the visit settles it. A gasket that has taken a set stops sealing at the hinge end first and loads the box with damp air continuously. A kitchen sitting warm and still all summer can also sweat a cabinet that is working correctly, so room temperature and humidity are logged too.
- Can a gasket be adjusted instead of replaced?
- Sometimes. Hinge play, closer action and cabinet level all move the perimeter, and a cabinet that has racked on century-old framing can often be brought back without new rubber. Where the gasket has hardened or pulled out of its retainer, adjusting it only postpones the same call.
- What does a door seal repair cost?
- $80 flat to diagnose. A door gasket or seal replacement runs $230–$620, parts and labour together. Levelling and hinge work appear as their own lines on the same written estimate, so you can see what is rubber and what is carpentry before anything is ordered.
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 door seal and condensation work
4.5 out of 5 across 71 customer reviews. Read every one of them.
The frame sweated all summer and the cabinetry beside it was starting to mark. A seal that had gone hard at the hinge end, plus a closer that needed setting, and the sweating stopped.
Clementina P.2026-04-27
Our panel had dropped enough that the door caught on the way shut. He shimmed the hinge, reset the cam and lined the panel back up with the cabinetry either side of the opening.
Lavinia B.2025-10-08