Whether it is an under-bench unit, a glass door display fridge or a walk-in coolroom, every commercial refrigeration system works on the same basic cycle. Understanding the main parts makes it easier to describe a fault to a technician and to understand the repair.
How Does a Commercial Fridge Work? The Short Answer
A commercial fridge moves heat out of the cabinet using a refrigerant cycle: the compressor pumps refrigerant to the condenser, where it releases heat and becomes a liquid; an expansion valve or capillary tube drops its pressure; and in the evaporator inside the cabinet, it absorbs heat and boils back into a gas. Fans, a controller, sensors and a defrost system manage the cycle.
The Main Working Parts
Refrigerant
The working fluid that carries heat. It is not used up. If a system is low, there is a leak that must be found and repaired by an ARC-licensed technician.
Compressor
Raises the pressure and temperature of the refrigerant gas and drives it around the system. Common problems: overheating, short cycling, failure to start. See commercial compressor problems.
Condenser and condenser fan
Release heat from the refrigerant to the surrounding air. On self-contained units the condenser sits in the base or top of the cabinet; on larger systems it may be a remote condensing unit. Common problems: dirty coils, failed fans.
Expansion valve or capillary tube
Meters refrigerant into the evaporator at low pressure. Larger systems use thermostatic or electronic expansion valves. Common problems: blockages, incorrect adjustment, failed valves.
Evaporator and evaporator fan
Absorb heat inside the cabinet and circulate cold air. Common problems: ice build-up, fan failures, leaks.
Controller and sensors
Monitor cabinet and coil temperatures and control the compressor, fans and defrost. Common problems: faulty sensors, alarms, incorrect settings.
Defrost system
Keeps the evaporator free of ice using timed or on-demand defrost, with heaters or off-cycle defrost. Common problems: iced coils, water leaks.
Gaskets, doors and drains
Keep cold air in and remove defrost water. Common problems: split gaskets, sagging doors, blocked drains.
Need a technician who knows commercial systems? Call Ace Fridge Repairs on 0452 462 556.
Why This Matters for Repairs
Many symptoms look similar: a warm cabinet can come from a dirty condenser, a failed fan, an iced evaporator, a faulty sensor, a refrigerant leak or a failing compressor. A methodical diagnosis finds the real cause. See common commercial fridge problems and how fridges are diagnosed.
Commercial Refrigeration Repairs Across Sydney
Ace Fridge Repairs repairs commercial fridges, freezers and coolrooms from Fisher and Paykel, Skope and most other major brands across Greater Sydney, including Parramatta and Seven Hills, from 93B Pagoda Crescent, Quakers Hill NSW 2763. Repairs carry a 12-month warranty on parts and labour.
For commercial fridge repairs, call 0452 462 556, 24/7.
Frequently Asked Questions
What are the main parts of a commercial fridge?
The compressor, condenser and condenser fan, expansion valve or capillary tube, evaporator and evaporator fan, controller and sensors, defrost system, gaskets and drains.
Does a commercial fridge need regassing?
Not routinely. Refrigerant is not used up, so low refrigerant indicates a leak that must be repaired by an ARC-licensed technician.
What is a remote condensing unit?
On larger systems such as coolrooms, the compressor and condenser are located outside the cabinet, often on a roof or in a plant room.