Controller Operation • 45
CONTROLLER OPERATION
Conditions that Trigger the Temperature alarm
If the controller alarm sounds during the scheduled defrost times, please allow an additional one-hour recovery time before calling
for service. If the alarm sounds outside of the scheduled defrost times, please review the following checklist. If all items have been checked
and the case still does not work properly, submit a service request.
Cases with electronic controls (a digital display shows through a cutout in the shroud above the doors) have a 1-hour alarm delay after defrost.
The controller has a 10ºF high alarm set point for freezers and 50ºF for coolers. The controller has a -20ºF low alarm set point for freezers and
28ºF and 30ºF for coolers. The alarm will sound when the sensed temperature is at or above the high alarm set point for a period of 1 hour. If
the temperature drops below the high alarm set point during this 1 hour, the alarm timer will reset. If the case is in defrost, the electronic display
will read “DEF”.
CHECKLIST: COMMON TRIGGERS FOR THE TEMPERATURE ALARM
1. Check the circuit breakers for the cases. Tripped circuit breakers will cut off the power to the cases and to the alarms. DO NOT TURN OFF
CASE REFRIGERATION OVERNIGHT WHEN CLOSING THE STORE.
2. For reach-in cases, check the following before entering a service request:
a. Defrost lasts 30-40 minutes for freezers and 45 minutes for coolers. Determine when the defrost cycle started (see the Defrost
Schedule shippped with the case). If alarm sounds during scheduled defrost, wait 1 hour and re-check status before calling service.
b. On freezers, the fans turn off during defrost and shortly after defrost. On coolers, the fans and lights continue to run during defrost.
c. Has the case just been stocked? (Warm product will take 24 hours to cool down.)
d. Is the case heavily shopped? (Frequent door opening will warm the case.)
e. are the return air grills blocked by product or other objects?
3. For open multi-decks, check the following before entering a service request:
a. Defrost lasts 30 minutes for open multi-decks. Determine when the defrost cycle started (see the Defrost Schedule shippped with the
case). If alarm sounds during scheduled defrost, wait 1 hour and re-check status before calling service.
b. Is the case located near vents, drafty areas, or other cases that would disrupt the air curtain?
c. Is the case located near sources of heat or humidity?
d. Has the case just been stocked? (Warm product will take 24 hours to cool down.)
e. are the store ambient conditions too warm or humid for proper case operation?
f. Is the case packout adequate to sustain optimal operating conditions?
g. are the return air grills blocked by product or other objects?
