If your Traulsen isn’t holding temperature, the most likely culprits are the evaporator fan motor, a dirty condenser, or a failed control board. Start with the simplest checks first before assuming it’s the compressor.
Most Common Causes, in Order of Likelihood
Dirty or blocked condenser coils cause more “not cooling” calls than anything else. Traulsen units in busy prep kitchens accumulate grease and dust fast. When the condenser can’t shed heat, the whole refrigeration cycle struggles and cabinet temps climb. You’ll often notice the compressor running hot and the unit cycling on its high-pressure cutout. Pull the grille, look at the coil. If it’s packed with debris, that’s your first move.
Evaporator fan motor failure is the second thing to check. The evaporator fan circulates cold air through the cabinet. If the fan stops, the coil may still get cold but the cabinet warms because air isn’t moving. Most Traulsen reach-ins cut the evaporator fan when the door is open, so you need to press and hold the door switch to test it. No spin, or a grinding noise, points to a failed motor or a blade seized from ice buildup. Motor replacement means pulling the evaporator panel, disconnecting wiring, and sourcing the right motor for that unit. It’s a tech job.
Control board issues are more common on Traulsen than people expect. The INTELA-TRAUL electronic controller manages defrost cycles, fan timing, and temperature setpoints. When it starts failing, you’ll see erratic temperature swings, a display that’s stuck or flickering, defrost that runs too long or not at all, or the unit hunting for a setpoint it never reaches. A board fault can mimic almost any other symptom. Replacement requires matching the exact board revision and reconfiguring setpoints correctly, which isn’t something to guess through on a unit holding perishable inventory.
Defrost system problems show up as frost buildup on the evaporator coil, which eventually blocks airflow entirely. Traulsen’s defrost heater, defrost thermostat, or the termination switch can fail individually. Evaporator sensor failures are also common on these units and can prevent defrost from completing. If you see heavy ice sheeting on the evaporator, that’s a sign defrost isn’t running. Powering the unit off overnight with the doors propped open is a useful diagnostic: if temperatures recover after a manual defrost, the defrost system is where the problem is. Tracking down and replacing the failed component is electrical work inside the unit.
Door gaskets and door alignment are easy to overlook. A gasket that’s torn, compressed flat, or warped lets warm moist air in constantly. The unit overcools trying to compensate, and ice builds up at the door perimeter. Check with a dollar bill: close the door on it and pull. If it slides out with no resistance, the gasket isn’t sealing.
Low refrigerant is less common but possible, especially on older units or after any physical damage to the cabinet. Signs are a partially frosted evaporator (frosted only partway along the coil) and a compressor that runs continuously without pulling temps down. Refrigerant work requires EPA certification and pressure gauges. There’s no homeowner workaround here.
How a Tech Diagnoses It
When I send a tech to a Traulsen call, the sequence usually goes: check condenser condition, verify fans are spinning (pressing the door switch with the door open), pull up the controller’s alarm history, check defrost cycle timing, then measure suction and discharge pressures. The INTELA-TRAUL controller on most Traulsen models stores fault history, which often points directly at the problem without guessing.
A tech will also check supply voltage. Traulsen units are sensitive to voltage fluctuations. Low voltage causes the compressor to draw high amperage and overheat, tripping the thermal overload. If the unit keeps shutting off and recovering, check what else shares that circuit, and don’t keep resetting the overload without finding out why it’s tripping. Repeated resets can destroy a compressor.
What’s Safe to Check Before You Call
These are reasonable owner-level checks worth doing before a tech arrives:
- Condenser coil: With the unit unplugged, clean the coil. Traulsen recommends every three months as a baseline. Kitchens near fryers or griddles usually need it more often.
- Condenser clearance: On the G-Series, the condensing unit is top-mounted with a front-facing louver. Make sure nothing is blocking overhead airflow. Traulsen specifies at least 12 inches of clearance above the condensing unit.
- Evaporator fan: Press the door switch with the door open. Is it spinning? Is there heavy ice around the fan assembly?
- Door gaskets: Check for tears, gaps, flat spots, or hardening.
- Controller display: Is it showing a fault code or alarm? Write down exactly what it says before calling.
That’s the limit of safe owner-level checks. Fan motor replacement, board replacement, defrost component swaps, refrigerant handling, and compressor diagnosis all need a licensed commercial refrigeration tech. Getting any of those wrong risks damaging other components, and in most cases voids what’s left of the warranty.
Call Us
If the condenser is clean, the fans are running, and the unit still isn’t holding temp, the problem is deeper and it’s time to call a tech. A warm Traulsen in a commercial kitchen isn’t something to wait out.
Bay Area Refrigeration Service handles Traulsen commercial equipment across the Bay Area. Our techs know the INTELA-TRAUL controller system and carry common Traulsen parts. We’ll get you on the schedule fast, often same or next day when we can. Give us a call.