A breaker that trips once can be a fluke, like a power flicker or a storm. A cooler or freezer that trips its breaker again and again is telling you something is wrong. Usually the compressor is struggling to start, or a motor, heater or wire has a fault. Resetting it over and over can turn a small repair into a burned-out compressor, so it helps to know what to look for and when to stop.
Pay attention to when it trips
The timing is one of the most useful things you can tell a technician. Write it down before you call:
- Right away when you reset it: this points to a short circuit or a part that has failed to ground, often in the compressor, a fan motor or the wiring.
- A few seconds after the compressor tries to start: the compressor may be hard-starting. A weak start capacitor or a bad start relay is a common cause, and so is a compressor that is wearing out.
- After running for a while: a motor overheating, a loose connection heating up, or a dirty condenser making the system work too hard can all build up until the breaker gives.
- Only during defrost (freezers): a shorted defrost heater or wet wiring around the evaporator is a likely suspect.
What staff can safely check
- Reset it once, not over and over: if the breaker trips again, leave it off. Repeated resets put a lot of stress on a compressor that is already struggling.
- Extension cords and shared circuits: plug-in units like reach-ins, prep tables and bar coolers should be on their own proper outlet, not an extension cord or power bar. A new piece of kitchen equipment added to the same circuit can be enough to start the trips.
- Water near electrical parts: look for leaks, mopping water or melting ice near the unit's electrical box or cord. Don't touch anything wet; just note it for the technician.
- A dirty condenser: on self-contained units, a coil caked with dust and grease makes the compressor run hot and draw more power. See why a fridge runs warm while the compressor keeps going.
- Sounds when it tries to start: a loud hum, a click every few minutes, or a buzz followed by the breaker tripping is worth mentioning when you call.
Don't open electrical panels, unit control boxes or the compressor compartment. Commercial refrigeration often runs on 208 or 240 volt power, and those checks belong with a technician.
Protect your product first
If the unit is off, move the most valuable and most temperature-sensitive product to another cooler or freezer and keep the doors of the dead unit closed. Our guide on what to do when a restaurant fridge breaks down walks through the first steps.
What a technician will look at
- Voltage at the unit, and whether the breaker and wire size suit the equipment.
- The start capacitor, start relay, contactor and overload.
- Compressor windings, to see if the compressor is shorted or grounded.
- Fan motors and defrost heaters, which can also trip a breaker.
- Loose, burned or wet connections in the unit and at the disconnect.
Many breaker problems come down to a start part, a fan motor or a wiring fix. If the compressor itself has failed, the next question is whether to replace the compressor or the whole unit. Our article on when to replace a walk-in compressor covers how to weigh that decision.
Get it running safely
YYC Mechanical handles commercial refrigeration repair for walk-ins, reach-ins and freezers across Calgary and nearby towns. If the breaker won't stay on and product is at risk, leave it off and call our 24/7 emergency line.