Used -80 C Freezer: What to Check

In a used ultra-low temperature freezer, first check that it reaches -80 C and holds it steadily. Then check the door seals and ice build-up, alarms and temperature logging, the refrigeration system, and the capacity and footprint against your space.

Temperature and stability

Ask for the pull-down time and long-term stability. A freezer that struggles to reach -80 C or warms quickly when the door opens can put samples at risk.

Seals, ice and doors

Outer door seal and inner doors
Ice build-up around the door: a sign of a weak seal
Handle lock and key

Refrigeration and controls

Compressors and refrigeration system (usually cascade)
Temperature alarms and contacts for a monitoring system
Working display and controller
Ventilation space around the freezer, which produces a lot of heat

Frequently asked questions

How long does a -80 freezer take to reach temperature?

It depends on the model and capacity, usually several hours. Ask for the manufacturer figure and check it at start-up.

Does it need a special location?

It needs ventilation space around it and a suitable power supply, because it releases a lot of heat.