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Commercial Reach-In Refrigerator: Noisy — Causes & Fixes

Compiled by Resultex Media Group · Editorially reviewed · Last verified August 2026

Quick answer: The most common causes are an out-of-level cabinet or loose panels/louvers vibrating, a fan blade contacting frost or debris, or debris in the condenser fan; a loud compressor that hums but won't start is a separate electrical fault.
Food safety: Noise alone is not a food-safety issue. Verify the cabinet is still holding 41°F or below (FDA Food Code 3-501.16); if a failing fan or compressor has let it warm up, apply the danger-zone/4-hour discard rule to the product. Note: returning food to 41°F does not by itself make it safe. If the time/temperature history is unknown, segregate the product and follow your food-safety plan; the FDA Food Code’s time-as-a-public-health-control provisions require specific written procedures, and local health-department requirements may differ. When safety cannot be verified, discard it.

Check in this order (5-minute diagnostic)

Work top to bottom — the quickest, most-likely checks are first.

  1. Cabinet not level / loose panel or louver. Confirm the unit is level and all panels, the louver/grille, and screws are tight. Rattling often traces to a loose grille or panel resonating with the compressor/fan.
  2. Condenser-fan or evaporator-fan obstruction / dirty fan. With power OFF, look for debris on the fan blade or ice contacting the evaporator fan. True's condenser cleaning procedure includes cleaning the fan blades.
  3. Compressor hums but will not start / failing motor or start components. Loud hum or buzz from the compressor with no cooling. Traulsen's chart lists 'Compressor hums but won't start' with the remedy to 'Contact service.'

Likely causes, checks & fixes

Likely causeHow to checkWhat to doWho
Cabinet not level / loose panel or louverConfirm the unit is level and all panels, the louver/grille, and screws are tight. Rattling often traces to a loose grille or panel resonating with the compressor/fan.Level the cabinet and tighten the louver assembly and panel screws.DIY-safe
Condenser-fan or evaporator-fan obstruction / dirty fanWith power OFF, look for debris on the fan blade or ice contacting the evaporator fan. True's condenser cleaning procedure includes cleaning the fan blades.Disconnect power and clear debris from the fan and coil; if a fan is contacting ice, defrost the unit. If a fan motor is noisy/failing, have it replaced. · see: iceBasic
Compressor hums but will not start / failing motor or start componentsLoud hum or buzz from the compressor with no cooling. Traulsen's chart lists 'Compressor hums but won't start' with the remedy to 'Contact service.'Have a qualified service technician diagnose the compressor start components (relay/capacitor) or compressor. This is a high-voltage/sealed-system repair. · see: iceTechnician

Who can do it: DIY-safe owner-doable · Basic simple part swap · Technician refrigerant/gas/electrical — call a licensed pro.

How to do the safe fixes

Owner-doable procedures only. Anything on the "Technician" list above needs a licensed pro.

Clean the condenser coil DIY-safe
  1. Disconnect power to the unit (unplug it or switch off and lock out the breaker).
  2. Remove the lower louver/grille assembly (True: remove the four corner screws; Traulsen: remove the two screws at the bottom and pivot the louver up).
  3. Use a stiff-bristle brush to loosen dust, lint, and grease from the condenser fins, working in the direction of the fins.
  4. Vacuum the loosened debris from the coil, fan blades, and cabinet floor; optionally blow the coil clear with compressed air (never use a metal tool that could bend fins or puncture tubing).
  5. Reinstall the louver/grille and screws.
  6. Restore power and confirm the compressor and fan run.

· Tools: Screwdriver, Stiff-bristle brush, Shop vacuum with brush attachment, Compressed air (optional), Gloves and eye protection · Source: True GDM Series Technical & Service Manual; Traulsen G-Series Owner's Manual

Replace a door gasket DIY-safe
  1. Bring both the unit and the new gasket to room temperature before starting (Traulsen: 'both the unit and the gasket itself must be at room temperature').
  2. Remove the old gasket: 'grasp it firmly by one corner and pull it out' (Traulsen). Most reach-in gaskets are a dart/push-in type held in a channel around the door.
  3. Clean the gasket channel and door edge.
  4. Install the new gasket by seating the four corners first, using a rubber mallet or a hammer with a block of wood.
  5. After the corners are seated, work toward the center from both ends, gently tapping until the gasket is fully seated all the way around (Traulsen).
  6. Close the door and check for an even seal all around; a dollar-bill or paper drag test at several points confirms the seal.

· Tools: Replacement gasket (correct part number), Rubber mallet (or hammer with a wood block), Warm water · Source: Traulsen G-Series Owner's Manual

Manually defrost an iced-up cabinet DIY-safe
  1. Move all product to another working cooler so it stays at or below 41°F.
  2. Disconnect power (or switch off) and prop the doors open.
  3. Let all frost/ice melt naturally—do not chip ice off the evaporator with tools, which can puncture the coil.
  4. Mop up melt water and clear/flush the condensate drain so water drains out.
  5. Restore power, let the cabinet return to setpoint, then reload product.
  6. If heavy frost returns quickly, the door seal or defrost system needs attention (see the ice/frost symptom).

· Tools: Towels, Another cooler for product · Source: True / Traulsen / Hoshizaki use-and-care guidance (manual defrost)

Clear a clogged condensate drain and clean the drain pan DIY-safe
  1. Disconnect power to the unit.
  2. Locate the evaporator drain pan and the drain tube/line.
  3. Remove debris and standing water from the pan; wash it with warm water and a soft brush.
  4. Flush the drain line with warm water to clear any blockage so defrost water routes out of the cabinet (do not force rigid objects that could damage the line).
  5. Confirm the cabinet is level so water drains toward the pan, then restore power.

· Tools: Gloves, Warm water, Soft brush or flexible tube brush · Source: Traulsen G-Series Owner's Manual (evaporator drain/condensate system)

Reset / clear a clogged-filter or condenser alarm (Hoshizaki) DIY-safe
  1. Turn the power switch OFF and unplug the unit before cleaning (Hoshizaki: 'Before cleaning the unit, move the power switch to the OFF position and unplug the unit to prevent electric shock').
  2. Clean the air filter and/or condenser (Hoshizaki alarm remedy: 'Clean the air filter and/or condenser').
  3. Restore power; allow time for the sensor to reset, then press the RESET button—or turn the power OFF and then ON again to reset the unit.
  4. If the alarm returns after cleaning, have a technician investigate.

· Tools: Brush/vacuum for the filter and coil · Source: Hoshizaki Reach-In Instruction Manual

Adjust the temperature control / verify setpoint DIY-safe
  1. Place a calibrated thermometer inside the cabinet (or use an in-cabinet product simulator) rather than trusting the dial alone.
  2. If product is freezing, adjust the control to a warmer setting; if running warm, verify the setpoint is correct and not too high (Traulsen: readjust the control).
  3. After any change, allow the cabinet time to recover and re-check the thermometer before making further adjustments.
  4. If the cabinet will not hold within a few degrees of a correct setpoint, the thermostat/sensor or sealed system needs a qualified technician.

· Tools: Accurate thermometer · Source: Traulsen G-Series Owner's Manual (temperature control troubleshooting)

Stop and call a qualified technician if:
Repair or replace? A gasket, coil cleaning, or a simple part is almost always worth fixing. Weigh replacement when the unit needs a compressor or sealed-system repair and is roughly 8–10+ years old, or when repeated service calls approach the cost of a new unit. Compare current reach-in refrigerators →

Related reach-in refrigerator problems

Frequently asked questions

Why is my reach-in refrigerator noisy?

The most common causes are an out-of-level cabinet or loose panels/louvers vibrating, a fan blade contacting frost or debris, or debris in the condenser fan; a loud compressor that hums but won't start is a separate electrical fault.

When should I call a technician instead of fixing it myself?

Call a licensed technician for anything involving the sealed system, refrigerant, gas, or high-voltage wiring — for example: Compressor hums but will not start / failing motor or start components. These are diagnostic-only for an operator.

Is it worth repairing or replacing?

Simple fixes (gaskets, coil cleaning, a single part) are worth repairing. Consider replacing when it needs a compressor or sealed-system repair and is 8–10+ years old, or when repeat service calls near the price of a new unit.

Sources