The Freeaire Manual

Specifying Planning Installing Wiring Cooler Controller Commissioning & Troubleshooting Maintaining

Commissioning & Troubleshooting a System

These two things are closely related, as commissioning is just troubleshooting that is done right after a system is first installed. Most problems that occur will make themselves known in the first few days of a new installation. These are usually easily solved with an adjustment of one or more of the settings in the Cooler Controller. Sometimes, problems may not become apparent until humid summer weather arrives, or a big change in the refrigeration load is made. The installer should try to anticipate seasonal variations that would affect refrigeration, and only use settings that will work at anytime of the year. The temperature registered by the inside, evaporator, or outside sensor may be lowered by dipping it into a cup of ice water, or raised by using the warmth from your hand. This is sometimes useful in determining whether the Cooler Controller is operating correctly.

Once the optimum settings for a particular Freeaire installation have been arrived at, there should be no need for further changes. Review operation, user menu adjustments, and maintenance procedures with owner or manager. Stress close monitoring and possible need for adjustment during start-up period.

SYMPTOM: Temperature in walk-in is too cold or too warm. POSSIBLE CAUSE#1: The LOW LIMIT setting of the Cooler Controller is too low or too high. SOLUTION: Adjust to a lower or higher setting. Access the User Menu by holding down all three white buttons for 5 seconds. When the LOW LIMIT setting is displayed, use the + or - button to change the setting. Go to Cooler Controller: User Menu: Low Limit

POSSIBLE CAUSE #2: The inside temperature sensor has failed. SOLUTION #2: Test the sensor to determine its accuracy. (Ice water should read 32-33°F or 0°C.) Replace if necessary.

POSSIBLE CAUSE #3: The compressor system has failed. SOLUTION #3: Have a refrigeration technician check out its operation.

SYMPTOM: Condensation forms on the outside of the reach-in doors during humid weather. CAUSE: The door heaters are not energized. SOLUTION #1: Switch on the DOOR HEATERS toggle switch at the Cooler Controller. Check to see that the door heater circuit breaker is closed in the main electrical panel. Also check to see that the toggle switches on the door frames themselves are switched on.

SOLUTION #2: Adjust the HUMIDISTAT to a lower setting. Go to Wiring: Low Voltage Wiring- Humidistat

SYMPTOM: Frost build-up on the evaporator coils. POSSIBLE CAUSE #1: Incorrect evaporator temperature sensor placement. The sensor is not located in the last part of the evaporator coils to be completely defrosted and the defrost cycle is ending too soon. SOLUTION #1: Re-position the sensor to that part of the coils that stays frosted up. In a cooler, if there is one sensor for two or more evaporator fan units, the sensor may have to be moved to the unit that is most frost-prone. As the evaporator coils may be clogged with ice in the place where a sensor needs to be re-positioned, note the spot where there is the greatest accumulation of ice. Take a large slotted screwdriver and heat the tip with a propane torch. Gently insert the screwdriver into the ice so that a hole is melted out between two fins and right next to a refrigerant pipe. Reheat the screwdriver as necessary to deepen and enlarge the hole to fully insert the sensor into the ice. Secure the sensor wire so that the sensor will not fall out of the hole when the ice is melted. Go to Wiring: Evaporator Sensor. Begin a defrost cycle by accessing the Installer Menu. Go to Cooler Controller: Installer Menu: Start Defrost Now. In a cooler, this will switch the evaporator fans on and switch the compressor off until the evaporator sensor(s) indicate(s) a temperature equal to 1 degree less than the inside temperature and the defrost period ends. In a freezer, this will stop the evaporator fans and energize the electric defrost heaters. Once the defrost period ends, make sure that there is no ice left. If there is ice remaining, move the evaporator sensor again to that spot and begin another defrost cycle.

POSSIBLE CAUSE #2: The maximum allowable evaporator temperature setting to end defrost is too low, ending the defrost cycle prematurely. SOLUTION #2: The MAX EVAP TEMP TO END DEFROST setting should be adjusted to a higher temperature. Go to Cooler Controller: Installer Menu: Max Evap Temp.

POSSIBLE CAUSE #3: The defrost period is "maxed out on time", which has ended the defrost cycle before the evaporator temperature could end it. There will be a message in the display window reading "MAX TIME ENDED LAST DEFROST" if this is the case. SOLUTION #3: Raise the MAX TIME TO END DEFROST setting in the Installer Menu to a higher number. Go to Cooler Controller: Installer Menu: Max Time to End Defrost.

POSSIBLE CAUSE #4: Variation over time of the place of where ice on the coils forms. SOLUTION #4: The EXTRA DEFROST TIME setting should be adjusted to a higher number of minutes. Go to Cooler Controller: Installer Menu: Extra Defrost Time.

POSSIBLE CAUSE #5: Too much time between defrost cycles. The ice would have all formed completely since the last defrost cycle. SOLUTION #5: The COMP OP TO START DEFROST setting should be adjusted to a fewer number of hours. Go to Cooler Controller: Installer Menu: Comp Op to Start Defrost.

POSSIBLE CAUSE #6: The evaporator temperature sensor has failed. SOLUTION #6: Test the sensor to determine its accuracy. (Ice water should read 32-33°F.) Replace if necessary.

SYMPTOM: The defrost cycle lasts too long, allowing the walk-in too get too warm. POSSIBLE CAUSE #1: Too much extra defrost time. SOLUTION #1: The EXTRA DEFROST TIME setting should be adjusted to a lower number of minutes. Go to Cooler Controller: Installer Menu: Extra Defrost Time.

POSSIBLE CAUSE #2: Too high a maximum temperature to end defrost. SOLUTION #2: The MAX EVAP TEMP TO END DEFROST setting should be adjusted to a lower temperature. Go to Cooler Controller: Installer Menu: Max Evap Temp.

SYMPTOM: The Cooler Controller behaves erratically or gets "stuck" and can't be adjusted. POSSIBLE CAUSE: This could happen during a bad thunderstorm or extreme voltage surge. SOLUTION: "REBOOT" the controller by switching the first switch on the left (COOLER CONTROLLER) OFF and then ON again. Check the settings in both the User and Installer menus, and re-enter any incorrect settings.

SYMPTOM: The Cooler Controller's display window has the following blinking message: MEMORY FAULT CHECK ADJST MODE. POSSIBLE CAUSE: If there has been a voltage surge, one or more of the custom settings (i.e. not default settings) may have been lost from the Cooler Controller¹s memory and the above slowly blinking message will appear. Also any other window scrolled to or accessed through the User Menu will continue to blink until the Installer menu is accessed. Meanwhile, the default settings will be operative. SOLUTION: Enter the User and the Installer Menus and re-enter any incorrect settings. If you are still having problems: contact us here at R.H. Travers Company at 802-496-5205 and we will try to come up with a solution.

SYMPTOM: Condensation drips from the exhaust or intake damper housings during hot, humid weather. CAUSE: There are no summer plugs are not in place and air is leaking around the dampers. SOLUTION: Install and adjust the summer plugs or cap to insure an airtight fit. Rotating the plugs as they are inserted usually results in a very snug fit.

SYMPTOM: The amount of outside air coming into the walk-in is noticeably less than before. CAUSE #1: The filter is dirty. SOLUTION #1: Replace the filter. Go to Catalog of Options: Filter.

CAUSE #2: The exhaust fan is not operating . SOLUTION #2: Check electrical connections. Go into the Installer Menu of the Cooler Controller and test outside air system operation in OUTPUT TESTING.

SYMPTOM: The bottom of the walk-in is colder than the top, perhaps causing freezing. CAUSE #1: The circulating fan is not operating when the evaporator fans aren't. SOLUTION #1: Check electrical connections. Go into the Installer Menu of the Cooler Controller and test circulating fan operation in OUTPUT TESTING. Go to Cooler Controller: Installer Menu: Output Testing.

CAUSE #2: The (upflow) circulating fan pipe is blocked. SOLUTION #2: Remove blackage.

SYMPTOM: The Outside Air System runs at the same time as the compressor and evaporator fans. CAUSE: The refrigerating load is too great for the outside air fans at this outside temperature, so the compressor has come on to help out until the walk-in cools down. THIS IS NOT A PROBLEM! SOLUTION: None needed.

Specifying Planning Installing Wiring Cooler Controller Commissioning & Troubleshooting Maintaining