Inadequate cooling on walk in freezer

If your Traulsen 31300 freezer is cooling down to 28°F but not going below that temperature, and the compressor runs continuously except during the defrost cycle, there are a few tests you can perform to help diagnose the issue before considering replacing the expansion valve. Here are some steps to follow:
1. Check Airflow: Ensure that the airflow inside the freezer is not obstructed by any items or ice buildup. Verify that the evaporator coil is clean and not blocked. Poor airflow can lead to inadequate cooling.
2. Temperature Control Setting: Confirm that the temperature control setting on the freezer is correctly set to the desired temperature. Make sure it is not accidentally set too high or too low.
3. Condenser Coil Cleaning: Clean the condenser coils located either at the back or underneath the unit. Dust and debris accumulation on the coils can reduce cooling efficiency. Use a soft brush or vacuum cleaner to remove any dirt or debris.
4. Condenser Fan Operation: Check if the condenser fan is running properly. The condenser fan helps dissipate heat from the system. Ensure it is spinning freely and not obstructed. If it's not working, it may need to be replaced.
5. Check for Refrigerant Leaks: Perform a thorough inspection of the refrigerant lines and connections for any signs of leaks, such as oil spots, bubbles, or hissing sounds. If a refrigerant leak is suspected, it could be affecting the cooling performance, and repairing the leak and recharging the system may be necessary.
6. Pressure and Temperature Readings: To determine if the expansion valve is the culprit, you may need to take pressure and temperature readings at different points in the refrigeration system using specialized equipment. These readings can help identify any irregularities or inefficiencies in the system.
7. Consult with a Professional: If you're unsure about performing these tests or interpreting the results, it is recommended to seek assistance from a professional refrigeration technician. They will have the expertise and necessary tools to accurately diagnose the issue and provide appropriate solutions.
By conducting these tests and inspections, you can gather more information to make an informed decision about replacing the expansion valve or pursuing other potential causes for the inadequate cooling.

evap temps usuall run 10-15 degrees below the box temp.This a generally accepted rule of thumb.

Check the seal first. Then check the freon. If it's R-12, you can go to the auto parts house. They have a bottle with a hose to add freon. You put it in on the "suction" low side with the unit running. you can tell when it has enough by feeling the low line be cold and teh high pressure line is warm to hot

Good day,
The first step is to check to see if the fan motors in the evaporator cooling assembly are blowing.
The second step requires the use of compound gauge set. You will need to determine what type of refrigerant the unit runs on and what the high and low pressure readings are when the unit is on and running.

Hi,
That would be a plugged filter, plugged cap tube...or TXV whatever it has...

heatman101

no don't do that sounds like the drain tube going to the defrost pan is not in properly remove front grate and inspect to see if tube is off to one side if you completely seal the void that is required on operating frig's if has no air flow to cool the compressor will overheat and shorten the life or not cool properly

The 3 beeps indicates that the freeze cycle is longer than 60 minutes. with the suction pressure at 20, it sounds like low on charge (freon). I believe this is an R 404-A unit. Other things to look for are: Stuck float switch (in the up position), Water valve leaking, hot gas valve leaking, txv not feeding properly, weak compressor. Look at high side pressure too. It should not go below 210 psi during the freeze cycle. Low pressure should be in the middle to upper 40's psi.

Let me know if you need more.

If your products are already in the frozen state the answer is yes, you can make an immediate transfer. Normally a couple of hours run to allow the temperatures to stabilize is sufficient. The cool down run time also insures the the unit is functioning properly. If you plug it in and transfer the products right away make frequent checks to insure proper operation.

Check the evaporator coil for frost buildup on the back. Check for frost on the suction line, the biggest line returning to the compressor. If frost is evident at these places you have a defrost system problem. These systems have a defrost timer that defrosts the coil at preset times. Check the timer for proper operation by marking the position of the dial and check back to see if it changes. If it does not change position the timer motor is most likely bad. If the dial is not rotating automatically you can manually turn the dial in the direction of the arrow and put it through a defrost cycle.