Skip to main content
foodservicenerd

Commercial Reach-In Refrigerator: Not Cooling — Causes & Fixes

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

Quick answer: a common cause is a dirty condenser coil that can no longer reject heat; the next most likely causes are a poor door/gasket seal, blocked internal airflow, or the unit not being plugged in / a tripped breaker.
Food safety: Cold TCS (time/temperature control for safety) food must be held at 41°F or below (FDA Food Code 3-501.16). If the interior has risen above 41°F, check how long product has been in the danger zone (41°F–135°F): under the FDA Food Code, TCS food held above 41°F must be cooled back to 41°F or below within the allowable window or discarded, and food left in the danger zone for more than 4 hours must be thrown out. When in doubt about elapsed time, discard. Move product to a working cooler while the unit is repaired. 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. No power to the cabinet. Confirm the interior light and evaporator fan are off. True's troubleshooting guidance for a warm cabinet is to 'Check to make sure cabinet is plugged in, check to make sure circuit breaker is not tripped.' Continental and Traulsen list the same first checks (cord disconnected, breaker off).
  2. Dirty / clogged condenser coil. Pull the lower louver/grille and look at the coil; if it is matted with dust, lint, or grease the system cannot reject heat. True and Traulsen both list a dirty condenser as a cause of 'cabinet running warm' and 'prolonged/continuous operation.' Hoshizaki triggers a clogged-filter/condenser alarm for the same condition.
  3. Poor door or gasket seal / door left ajar. Inspect the gasket for splits, tears, or hardening and confirm the door pulls fully shut and the door-open indicator (if equipped) is not lit. Traulsen lists 'Poor door/gasket seal' as a cause of a too-warm food compartment.
  4. Blocked internal airflow / overloading. Look for product stacked against the interior back wall, over the evaporator, or blocking supply/return air ducts. Traulsen lists 'Blocked airflow' and improper product placement as causes; verify product placement.
  5. Temperature control set too high / needs recovery. Confirm the setpoint and whether warm product was recently loaded. Traulsen lists 'Control set too high' and 'Recent warm food added' as causes of a warm compartment.
  6. Iced-over / frosted evaporator coil (blocked, or a defrost fault). Look for a solid ice/frost mass on the evaporator behind the interior panel. True and Traulsen list an iced evaporator as a cause of warm running / continuous operation.
  7. Compressor not running / low refrigerant / sealed-system fault. Everything has power but the compressor never starts or short-cycles, or it runs constantly but the cabinet stays warm. True notes to verify supply voltage at the receptacle (should be within spec, e.g. 115V ±10%) before condemning components; a compressor that hums but will not start, or a low charge, points at the sealed system.

Likely causes, checks & fixes

Likely causeHow to checkWhat to doWho
No power to the cabinetConfirm the interior light and evaporator fan are off. True's troubleshooting guidance for a warm cabinet is to 'Check to make sure cabinet is plugged in, check to make sure circuit breaker is not tripped.' Continental and Traulsen list the same first checks (cord disconnected, breaker off).Make sure the unit is plugged into its dedicated grounded outlet and reset the tripped breaker. Do not use an extension cord (Traulsen: 'Do not under any circumstances... use an extension cord.').DIY-safe
Dirty / clogged condenser coilPull the lower louver/grille and look at the coil; if it is matted with dust, lint, or grease the system cannot reject heat. True and Traulsen both list a dirty condenser as a cause of 'cabinet running warm' and 'prolonged/continuous operation.' Hoshizaki triggers a clogged-filter/condenser alarm for the same condition.Disconnect power and clean the condenser coil (see the maintenance and how-to sections). This resolves many of warm-running complaints.DIY-safe
Poor door or gasket seal / door left ajarInspect the gasket for splits, tears, or hardening and confirm the door pulls fully shut and the door-open indicator (if equipped) is not lit. Traulsen lists 'Poor door/gasket seal' as a cause of a too-warm food compartment.Clean or replace the gasket and verify the door self-closes and seals. See the gasket how-to below. · see: doorDIY-safe
Blocked internal airflow / overloadingLook for product stacked against the interior back wall, over the evaporator, or blocking supply/return air ducts. Traulsen lists 'Blocked airflow' and improper product placement as causes; verify product placement.Redistribute product so air can circulate; do not block ducts or the evaporator. Allow recovery time after loading warm product (Traulsen: 'Allow recovery time').DIY-safe
Temperature control set too high / needs recoveryConfirm the setpoint and whether warm product was recently loaded. Traulsen lists 'Control set too high' and 'Recent warm food added' as causes of a warm compartment.Readjust the control to the correct setpoint and allow the cabinet time to recover before concluding there is a fault.Basic
Iced-over / frosted evaporator coil (blocked, or a defrost fault)Look for a solid ice/frost mass on the evaporator behind the interior panel. True and Traulsen list an iced evaporator as a cause of warm running / continuous operation.Manually defrost the unit (power off, doors open, let ice melt fully) as a first step; if frost returns quickly, the defrost timer/heater or a door-seal problem is the root cause and needs a technician to verify. · see: iceBasic
Compressor not running / low refrigerant / sealed-system faultEverything has power but the compressor never starts or short-cycles, or it runs constantly but the cabinet stays warm. True notes to verify supply voltage at the receptacle (should be within spec, e.g. 115V ±10%) before condemning components; a compressor that hums but will not start, or a low charge, points at the sealed system.This is a sealed-system / high-voltage diagnosis. Have an EPA Section 608-certified refrigeration technician verify the charge, compressor, and controls and make any repair. Do not open the refrigerant circuit yourself.Technician

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 not cooling?

a common cause is a dirty condenser coil that can no longer reject heat; the next most likely causes are a poor door/gasket seal, blocked internal airflow, or the unit not being plugged in / a tripped breaker.

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 not running / low refrigerant / sealed-system fault. 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