Reach-In Refrigerator Clicking, Buzzing or Loud Fans
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Updated October 14, 2026
Quick answer
A reach-in that clicks every few minutes without starting is usually failing to start the compressor: a bad start relay, overload or capacitor, or a compressor near the end. Loud fans are usually worn bearings or a blade hitting ice or debris. A clicking compressor needs a technician soon; it can overheat and fail completely.
Which noises are normal
A healthy unit makes a soft hum from the compressor, a steady whoosh from the fans, a click when the thermostat turns the compressor on and off, and occasional ticking as parts warm and cool during defrost.
Noises that are not
| Noise | Likely cause |
|---|---|
| Click, short hum, click again every few minutes | Compressor not starting: start relay, overload, capacitor or compressor |
| Grinding or squeal from inside the cabinet | Evaporator fan motor bearings |
| Ticking or scraping from inside the cabinet | Fan blade hitting ice |
| Rattle from the bottom grille | Condenser fan blade, loose shroud or debris |
| Loud buzz at the compressor | Electrical fault; switch off and call |
What you can do
- Clean the condenser coil. A compressor that overheats against a dirty coil trips its overload and clicks.
- Make sure the unit has its own outlet. Extension cords and shared circuits cause low voltage at start-up.
- Do not keep power-cycling a clicking compressor; each failed start heats it further.
Why compressors fail to start
A compressor needs a burst of current to start. A start relay or start capacitor gives it that boost, and an overload protector cuts power if it draws too much or gets too hot. When the relay sticks, the capacitor weakens or the voltage drops, the compressor hums briefly, overheats and the overload clicks it off. It cools, tries again, and repeats. Each failed start stresses the motor windings, which is why this needs attention quickly.
What a technician checks
- Supply voltage at the outlet while the compressor starts
- The start relay, start and run capacitors and the overload
- Compressor winding resistance and current draw
- Condenser condition and head pressure
A failed relay or capacitor is a modest repair. A failed compressor is not; see repair vs replace.
Fan noise in detail
Evaporator fans run inside the cold cabinet, often in moisture, and their bearings wear. A fan that squeals on start-up then quiets down is near the end. A fan blade that ticks against ice means the coil is icing, which is a defrost problem, not a fan problem. Condenser fans run in dust and grease; a wobbling blade or bent shroud is often the cause of a rattle.
Noises during defrost
Cracking, popping and dripping during a defrost are normal as ice melts and metal expands. If the noise lines up with the defrost symbol on the display, it is usually fine.
What to tell the technician
- How often it clicks, and whether you hear a hum between clicks
- Whether the cabinet is warming and how fast
- Whether the unit is on an extension cord or shares a circuit
- Whether the noise started after a power outage or breaker trip
- The brand, model and serial from the data plate
Electrical supply matters
Commercial refrigerators are designed for a dedicated outlet at the right voltage. Long or light extension cords, power strips and circuits shared with ice machines or microwaves drop the voltage when the compressor starts, which causes hard starts and early failure. If clicking began after equipment was added nearby, have the circuit checked.
Related problems
What each finding means
| Finding | Meaning |
|---|---|
| Clicking stopped after cleaning the coil | The compressor was overheating; monitor it |
| Clicking only when another appliance starts | Shared circuit or voltage drop |
| Clicking with a warm cabinet | Compressor not starting; call now |
| Fan noise stops when you open the door | Evaporator fan; door switch stops it |
| Rattle at the bottom grille | Condenser fan or loose panel |
Bay Area factors
Many older restaurant buildings in San Francisco, Oakland and downtown San Jose have limited electrical capacity, and equipment gets added over the years to the same circuits. Hard starts and clicking compressors are more common there. When you add equipment, check the circuit.
What not to do
- Do not keep power-cycling a clicking compressor.
- Do not run the unit on an extension cord.
- Do not bend or poke fan blades to stop a noise.
Prevention
Clean coils, a dedicated circuit and early fan replacement prevent most of these failures. A yearly professional inspection catches weak start components before they strand the compressor.
When to call a technician
Call now if the compressor clicks without running, if you hear a loud buzz, or if a fan grinds. Move perishable product if the cabinet warms.
Open 7 days, 8 AM to 5 PM, with emergency service until 9 PM. CA Lic. #776244.
Frequently asked questions
Why does my commercial refrigerator click on and off?
A click followed by silence every few minutes usually means the compressor tries to start and its overload trips. The start relay, capacitor or compressor itself is suspect.
Is a noisy evaporator fan an emergency?
Not yet, but bearings that grind usually fail within days or weeks, and the cabinet warms when they do.
Can low voltage cause clicking?
Yes. Long extension cords or overloaded circuits drop voltage when the compressor starts.
Is buzzing from a commercial fridge dangerous?
A loud electrical buzz at the compressor or control box can be an electrical fault. Switch the unit off and call.
How long can a clicking compressor last?
Not long; each failed start heats the windings. Call promptly.
Can a power outage cause clicking?
Yes; when power returns, a hard start can trip the overload, especially if the compressor restarts against high pressure.
Is a humming compressor normal?
A steady hum while running is normal; a hum followed by a click and silence is not.
Related guides
Sources
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