Frigidaire Freezer Frosting Over in Springdale

The call

A Springdale family with a large upright freezer in the garage — the second freezer, the one that holds the bulk shopping. It had been building frost on the rear wall for months, and the owner had been defrosting it by hand every few weeks. By the time they called, ice was forming again within days of a manual defrost.

They had assumed this was normal for a garage freezer, which is a common and understandable belief. It is not: a frost-free unit should never accumulate a sheet of ice on the back wall. If it does, the automatic defrost system has stopped working.

There was also a temperature symptom hiding behind the frost. The unit was holding around −11°C rather than −18°C, which is warm enough to degrade food quality slowly without anything visibly thawing.

Diagnosis

Frost-free freezers run a heater on a timed cycle to clear the evaporator coil. When that system fails, ice builds until air cannot pass through the coil, and the compartment warms even though the compressor runs constantly.

We removed the rear panel and found the evaporator encased in a solid block of ice — not frost, ice. Then, testing from the outside in:

• Defrost heater: open circuit. No continuity, so it had not been producing heat at all
• Defrost timer: not advancing through its cycle reliably
• Defrost thermostat within specification
• Evaporator fan running, but partly obstructed by the ice
• Defrost drain tube frozen solid, which is what happens once meltwater has nowhere to go

Two failed components rather than one, which is common: a timer that stops advancing means the heater is called on erratically, and a heater under that duty cycle fails sooner.

The fix

A controlled thaw first — several hours’ worth of ice, cleared properly with the panel off rather than attacked with a hair dryer, which warps plastic components at surprisingly low temperatures.

Then:

1. Defrost heater replaced
2. Defrost timer replaced
3. Drain tube cleared and flushed, then checked through a full defrost cycle to confirm meltwater actually leaves the cabinet

That last step is the one most often skipped. A blocked drain turns every future defrost cycle into a fresh sheet of ice, so fixing the heater without clearing the drain means the fault returns within weeks looking exactly as it did before.

Eighty-five minutes on site, most of it thawing and testing.

Outcome

The freezer settled at −18°C overnight and has stayed clear since.

We thought a garage freezer just did that. We have been defrosting it by hand for over a year.

Two things worth passing on:

Frost on the back wall of a frost-free unit is a fault, not maintenance. If you are defrosting manually more than once a season, something in the defrost system has failed.

A second freezer fails quietly. Nobody opens it daily, so a unit can drift warm for weeks before anyone notices — and in a garage, summer heat makes that worse. It is worth putting a thermometer in it and glancing at it when you pass.

Total: $247 before HST, covered by our 60-day parts and labour warranty.