Published October 16, 2026 · By the Wilprep Commercial Refrigeration Service Team
This guide draws on Wilprep's service team experience supporting reach-in, worktop, undercounter, and prep commercial refrigerators in restaurants, ghost kitchens, and institutional kitchens. It covers the most common commercial refrigerator problems, what you can safely fix yourself, and when to call a technician.
Quick Diagnosis: Find Your Refrigerator Issue
| Symptom | Most Likely Cause | First Action | DIY or Technician? |
|---|---|---|---|
| Not cooling | Dirty condenser coils | Clean coils with brush/vacuum | DIY |
| Running but warm inside | Blocked evaporator airflow | Rearrange product, clear vents | DIY |
| Uneven temperatures | Overloaded shelves or blocked fan | Leave 2–3 inches around evaporator | DIY |
| Excessive frost or ice | Failed defrost system or door gasket | Check defrost cycle and gasket seal | DIY / Tech |
| Water pooling inside or under unit | Clogged drain line | Clear drain line | DIY |
| Door won't stay closed | Worn gasket or loose hinge | Inspect gasket, tighten hinge | DIY |
| Compressor runs constantly | Dirty coils, bad gasket, or low refrigerant | Clean coils, check gasket | DIY / Tech |
| Loud noise or vibration | Fan obstruction or loose compressor mount | Inspect fan and mounting bolts | DIY / Tech |
| Refrigerator completely dead | Power interruption or tripped breaker | Check outlet and breaker panel | DIY |
| Temperature swings widely | Faulty thermostat or sensor | Verify with external thermometer | Technician |
Before You Call a Technician: The 3-Minute Triage
Many commercial refrigerator "emergencies" are not equipment failures. They are power issues, airflow problems, or simple maintenance oversights. Before you schedule a service call, run through this three-minute triage.
Step 1: Confirm power (30 seconds)
Verify the refrigerator is plugged in and the circuit breaker is not tripped. During cleaning, units frequently get unplugged and not plugged back in. Water splashed into a GFI outlet is a common cause of tripped breakers.
Step 2: Confirm the thermostat setting (30 seconds)
Someone may have adjusted the temperature during cleaning or restocking. Confirm the set point is correct. Most commercial refrigerators should hold between 34°F and 38°F (1°C to 3°C). Freezer compartments should be at 0°F (-18°C) or below.
Step 3: Confirm airflow is not blocked (2 minutes)
Overloading shelves, pushing boxes against the rear wall, or blocking evaporator vents restricts cold air circulation. This causes uneven temperatures and can freeze the evaporator coil. Rearrange product to leave 2–3 inches of clearance around the evaporator and ensure the fan blades spin freely.
If these three checks do not resolve the issue, use the symptom guide below to narrow down the cause.
Refrigerator Not Cooling Properly
This is the single most common commercial refrigerator complaint. The causes follow a predictable hierarchy.
Cause 1: Dirty Condenser Coils
The condenser coil releases heat from the refrigeration system. When dust, grease, and debris accumulate on the coil surface, heat cannot escape efficiently. The compressor runs longer and hotter, but the cabinet temperature rises.
What to do: Clean condenser coils monthly in high-grease environments. Use a soft brush and vacuum. For heavy grease, use a commercial coil cleaner. This is the highest-ROI maintenance task for any commercial refrigerator.
Cause 2: Blocked Evaporator Airflow
Inside the cabinet, the evaporator fan circulates cold air. If shelves are overloaded, boxes are pushed against the rear wall, or the fan blades are obstructed, cold air cannot reach all areas of the cabinet.
What to do: Rearrange product to leave 2–3 inches of clearance around the evaporator. Check that the evaporator fan blade spins freely. If the fan motor is noisy or not spinning, it may need replacement.
Cause 3: Door Gasket Failure
A worn or torn door gasket allows warm, humid air to enter the cabinet continuously. The refrigeration system cannot keep up. You may notice condensation around the door frame or frost buildup near the gasket.
What to do: Close the door on a dollar bill. If the bill pulls out easily, the seal is compromised. Gaskets are an inexpensive, user-replaceable part on most reach-in and worktop refrigerators. Order the correct gasket for your model.
Cause 4: Thermostat or Temperature Sensor Malfunction
A faulty thermostat produces inaccurate temperature readings, causing the compressor to cycle incorrectly. The refrigerator may run too long or not long enough.
What to do: Verify thermostat accuracy with an external thermometer placed in the center of the cabinet. If the reading diverges by more than 3–5°F, recalibration or replacement is needed. This is usually a technician task.
Cause 5: Defrost System Failure
If the refrigerator has an automatic defrost cycle, a failed defrost timer, heater, or termination thermostat can cause the evaporator coil to ice up. Airflow is blocked, and the cabinet warms even though the compressor runs.
What to do: Check for excessive frost on the evaporator coil. If the coil is heavily iced, manually defrost the unit and observe whether the defrost cycle restarts. If it does not, call a technician.
Cause 6: Refrigerant Leak or Compressor Issue
If coils are clean, airflow is clear, and the gasket is intact but the cabinet still won't hold temperature, you may have a refrigerant leak or compressor failure.
What to do: A compressor that runs constantly without cooling, or one that won't start at all, is a clear signal to call a licensed refrigeration technician. Refrigerant handling requires certification and special equipment.
Excessive Frost or Ice Buildup
Frost accumulation inside a commercial refrigerator usually points to one of three issues: a failed defrost system, a door seal problem, or high ambient humidity.
- Failed defrost system: If the unit has an automatic defrost cycle, verify it is functioning. A failed defrost heater or timer allows frost to accumulate on the evaporator coil.
- Door seal problem: A compromised gasket lets humid air in, which freezes on the coldest surfaces.
- High ambient humidity: In kitchens with steamers or dishwashers nearby, humidity can overwhelm the refrigerator's ability to stay dry.
What to do: If frost is beyond 1/4 inch, manually defrost the unit. Check the door gasket. If frost returns quickly, call a technician to inspect the defrost system.
Water Pooling Inside or Under the Refrigerator
Water on the floor or inside the cabinet is usually a drainage issue.
- Clogged drain line: Condensate from the evaporator drains through a line to a drain pan or floor drain. Food debris, grease, or ice can block it.
- Disconnected drain line: The drain line may have come loose during cleaning or movement.
- Cracked drain pan: In undercounter models, the drain pan can crack and leak.
What to do: Locate the drain line, usually at the rear of the evaporator housing. Clear any debris with a flexible brush or warm water. If the line is cracked or disconnected, replace it. Check the drain pan for cracks.
Loud Noise or Vibration
Commercial refrigerators are not silent, but new or worsening noises indicate a problem.
- Fan obstruction: A piece of debris or a misaligned fan blade can cause a scraping or rattling sound.
- Loose compressor mount: Compressor mounting bolts can loosen over time, causing vibration.
- Resonating tubing: Copper refrigerant lines can vibrate against the cabinet.
What to do: Unplug the unit and inspect the evaporator and condenser fans for obstructions. Tighten any loose mounting bolts. If the noise persists, call a technician—especially if it is coming from the compressor.
Door Won't Stay Closed or Seals Poorly
A door that hangs open or requires force to latch usually has a failed hinge or a worn door gasket.
- Loose or rusted hinges: Tighten hinge screws. If hinges are seized or broken, replacement is necessary.
- Compressed gasket: A gasket that is flat or cracked no longer provides a seal. Replace it.
- Auto-close mechanism: Some commercial refrigerators have a self-closing hinge. If it no longer closes the door, the hinge may need adjustment or replacement.
What to do: Inspect the gasket for cracks, tears, or compression. Replace if worn. Tighten hinge screws and check door alignment.
Temperature Swings or Inconsistent Cooling
Wide temperature swings—where the refrigerator cycles between too cold and too warm—are usually caused by:
- Faulty thermostat or sensor
- Defrost system issues
- Overloading or blocked airflow
- Door gasket failure
What to do: Verify with an external thermometer. Check airflow and gasket. If the problem persists, a technician should test the thermostat and defrost controls.
Compressor Runs Constantly
A compressor that never shuts off is trying to compensate for a problem elsewhere.
Common causes:
- Dirty condenser coils
- Failed door gasket
- Low refrigerant charge
- Restricted airflow
- High ambient kitchen temperature
What to do: Clean coils, check gasket, and ensure proper clearance around the unit. If the compressor still runs constantly, call a technician. Running a compressor to failure is far more expensive than an early repair.
Preventive Maintenance: The Best Troubleshooting Is Prevention
The operators who call for the fewest refrigerator repairs are the ones who follow a disciplined maintenance schedule.
Daily
- Check that doors close fully and gaskets seal
- Wipe down door frames and handles
- Verify the temperature display matches your target range
Weekly
- Inspect condenser coils for dust and grease
- Check for water pooling or unusual noises
- Verify temperature accuracy with an external thermometer
Monthly
- Clean condenser coils thoroughly
- Inspect door gaskets for cracks or compression
- Clear drain lines with warm water
- Lubricate hinges and moving parts
Quarterly
- Professional inspection of electrical components and refrigerant charge
- Calibrate thermostats
- Replace worn gaskets before they fail
When to Call a Technician — and What to Tell Them
Some issues are safely DIY. Others are not.
Call a licensed refrigeration technician for:
- Refrigerant leaks
- Compressor replacement
- Defrost system repair
- Thermostat or sensor replacement
- Electrical wiring issues beyond a tripped breaker
- Any repair that requires disassembling a sealed refrigeration circuit
When you call, have this information ready:
- Equipment make and model
- Serial number
- Specific symptom (not just "it's broken")
- What you've already checked
- When the problem started
This saves diagnostic time and helps the technician bring the right parts.
Need Support for Your Wilprep Refrigerator?
If your Wilprep commercial refrigerator needs service, our support team is here to help. For warranty claims, please have your proof of purchase and model/serial information ready. Replacement parts for Wilprep refrigerators—including gaskets, fan motors, thermostats, and drain lines—can be ordered directly through our parts portal.
Visit our contact page to reach our support team, or browse the warranty information for details on coverage and claims.
Frequently Asked Questions
My commercial refrigerator is running but not cooling. Is it always a refrigerant problem?
No. The most common causes—dirty condenser coils, blocked airflow, and failed door gaskets—are not refrigerant issues and can be addressed without a technician. Rule these out before assuming a sealed system problem.
How often should I clean my commercial refrigerator's condenser coils?
In a typical restaurant environment, monthly cleaning is the minimum. In high-grease operations, every two weeks is better. Coil cleaning is the single highest-ROI maintenance task for refrigeration equipment.
Why is there frost building up inside my refrigerator?
Frost usually means the defrost system is not working, the door gasket is leaking warm air, or the kitchen humidity is very high. Check the gasket first, then observe whether the defrost cycle runs. If frost returns quickly, call a technician.
Can I use a pressure washer to clean my commercial refrigerator?
No. Pressure washers force water into electrical components, control panels, and bearings, causing corrosion and short circuits. Use a damp cloth, mild degreaser, and soft brush.
My refrigerator is making a loud noise. Should I be worried?
A new or worsening noise should be investigated. Fan obstructions and loose compressor mounts are common causes. If the noise comes from the compressor, turn off the unit and call a technician.
How long should a commercial refrigerator last?
With proper maintenance, a quality commercial refrigerator can last 10–15 years. Dirty coils, failed gaskets, and neglected drain lines are the most common causes of premature failure.
The Bottom Line
Most "broken" commercial refrigerators aren't actually broken. They're dirty, blocked, unplugged, or overdue for basic maintenance. The triage steps and symptom guides above resolve the majority of common issues without a service call—saving you money and keeping your kitchen running.
For the issues that do require professional attention, addressing them early prevents small problems from becoming expensive failures. A $50 gasket replaced today prevents a $2,000 compressor replacement next month.
Wilprep Kitchen Equipment supplies commercial refrigerators—including reach-in models—to restaurants, ghost kitchens, and institutional kitchens across the United States. Our service team supports every unit we sell.
For parts, warranty support, or technical assistance, visit our contact page.
