Riverbend Refrigeration — +1 (904) 977-8701 — independent Sub-Zero refrigeration repair in Jacksonville, FL.
Booking: +1 (904) 977-8701 (tel:+19049778701). Source: https://jaxsubzero.com/repair/door-seal-and-condensation/

# Door seal and condensation

> Sweating panels, a warm cabinet corner or a door that will not stay shut. How we test a Sub-Zero gasket and hinge in a humid Jacksonville kitchen.

System: door and gasket. Cabinet: built in refrigerator.

## Symptoms an owner reports

- 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

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.

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Riverbend Refrigeration is an independent appliance repair company. We are not affiliated with, authorized by, or endorsed by Sub-Zero or its parent company. All brand names and model numbers are the property of their respective owners and are used only to identify the appliances we service.

Riverbend Refrigeration · +1 (904) 977-8701 · Jacksonville, FL