The Carel controller has a two-level menu system for programming the operation of the case. Level 1 program settings are the most frequently
accessed parameters. These items are used to make simple changes to the operation of the case. Level 2 program settings control more
complicated aspects of the case operation and, therefore, require the use of a password to gain access.
HOW TO CHANGE LEVEL 1 CONTROL SETTINGS
1. Press and hold the Program [Prg] button down for 5 seconds. “St” will be shown on the display.
2. Use the [Up] and [Down] arrows to move up or down the menu until you reach the parameter you intend to view or change. When the
proper code is displayed, press the [Set] button to view the current setting for that parameter.
3. Use the [Up] and [Down] arrows to change the value. Then press the [Set] button again to return to the menu.
4. The only exception to Step #3 is the real time clock, program code “tc”. In this case, you must press the [Set] button in order to access the
submenu of available settings for the “tc”parameter. Then press the [Up] and [Down] arrows to move up and down the submenu. Once
changes are made in this submenu, press the [Prg] button to get back to the main menu.
5. When nished making all necessary changes, you MUST press and hold the [Prg] button for 10 seconds to save them. Alternatively, if
you decide you do NOT want to save changes you’ve just made, simply stop pressing buttons for 30 seconds and the control will return to
normal operation, discarding any changes made.
HOW TO CHANGE LEVEL 2 CONTROL SETTINGS
6. Press and hold the [Prg] and [Set] buttons down for 5 seconds. The display will show a ashing “0”.
7. Use the [Up] arrow until the display reads “22” (this is the password), then press the [Set] button. The display will read “/P”.
8. Use the [Up] and [Down] arrows to move up or down the menu until you reach the parameter you intend to view or change. When the
proper code is displayed, press the [Set] button to view the current setting for that parameter. (You will notice the Level 1 program codes
are also found in this menu.)
9. Use the [Up] and [Down] arrows to change the value. Then press the [Set] button again to return to the menu.
10. The exceptions to Step #4 are the program codes “tc”, “td1”, and “td2”. In these cases, you must press the [Set] button in order to
access the submenu of available settings for these parameters. Once changes are made in this submenu, press the [Prg] button to get
back to the main menu.
11. When nished making all necessary changes, you MUST press and hold the [Prg] button for 10 seconds to save them. Alternatively, if
you decide you do NOT want to save changes you’ve just made, simply stop pressing buttons for 30 seconds and the control will return to
normal operation, discarding any changes made.
Note: Zero Zone should be contacted before working on changing settings. To be completed by a trained person only.
StSet point-10
rdDifferential6
dlDefrost interval12
dt1Defrost end temp70
dP1Defrost duration40
d/1Defrost probe temp(actual)
tc.yRTC yeartc.mRTC monthtc.dRTC day of monthtc.uRTC day of weektc.hRTC hourtc.mRTC minute-
Factory
Set
LOW TEMP
LEVEL 2
CodeName
/A2Probe 2 confi guration2
c1Min time between starts5
c2Min comp OFF1
c3Min comp ON1
d0Defrost type4
ddDrip time1
dnDefrost duration %100
ALLow temp alarm-20
AHHigh temp alarm10
F0Fan management2
F1Fan start temp30
H0Serial address1
H1Function of relay 410
td1.dDefrost time day 111
td1.hDefrost time hour 18
td1.mDefrost time minute 10
td2.dDefrost time day 211
td2.hDefrost time hour 220
td2.mDefrost time minute 20
Factory
Set
1 & 2 DOOR LOW TEMP
LEVEL 1
CodeName
StSet point-10
rdDifferential6
dIDefrost interval12
dt1Defrost end temp45
dP1Defrost duration30
d/1Defrost probe temp(actual)
tc.yRTC yeartc.mRTC monthtc.dRTC day of monthtc.uRTC day of weektc.hRTC hourtc.mRTC minute-
Factory
Set
1 & 2 DOOR LOW TEMP
LEVEL 2
CodeName
/A2Probe 2 confi guration2
c1Min time between starts5
c2Min comp OFF1
c3Min comp ON1
d0Defrost type0
ddDrip time1
dn Defrost duration %100
ALLow temp alarm-20
AHHigh temp alarm 10
F1Fan start temp30
H0Serial address1
H1Function of relay 410
td1.dDefrost time day 111
td1.hDefrost time hour 18
td1.mDefrost time minute 10
td2.dDefrost time day 211
td2.hDefrost time hour 220
td2.mDefrost time minute 20
Factory
Set
IM BOTTOM-MOUNTED COIL
LEVEL 1
CodeName
StSet point7
rdDifferential4
dIDefrost interval12
dt1Defrost end temp70
dP1Defrost duration40
d/1Defrost probe temp(actual)
tc.yRTC yeartc.mRTC monthtc.dRTC day of monthtc.uRTC day of weektc.hRTC hourtc.mRTC minute-
Factory
Set
IM BOTTOM-MOUNTED COIL
LEVEL 2
CodeName
/A2Probe 2 confi guration2
c1Min time between starts5
c2Min comp OFF1
c3Min comp ON1
d0Defrost type4
ddDrip time1
dn Defrost duration %100
ALLow temp alarm-20
AHHigh temp alarm 25
F0Fan management2
F1Fan start temp30
H0Serial address1
H1Function of relay 410
td1.dDefrost time day 111
td1.hDefrost time hour 18
td1.mDefrost time minute 10
td2.dDefrost time day 211
td2.hDefrost time hour 220
td2.mDefrost time minute 20
StSet point34
rdDifferential4
dt1Defrost end temp50
dP1Defrost duration30
d/1Defrost probe tempn/a
tc.yRTC yeartc.mRTC monthtc.dRTC day of monthtc.uRTC day of weektc.hRTC hourtc.mRTC minute-
MEDIUM TEMP
CodeName
/A2Probe 2 confi guration0
c1Min time between starts5
c2Min comp OFF1
c3Min comp ON1
d0Defrost type2
dlDefrost interval12
ddDrip time1
dnDefrost duration %100
ALLow temp alarm30
AHHigh temp alarm50
F0Fan management0
F1Fan start temp5
H0Serial address1
H1Function of relay 410
td1.dDefrost time day 111
td1.hDefrost time hour 18
td1.mDefrost time minute 10
td2.dDefrost time day 211
td2.hDefrost time hour 220
td2.mDefrost time minute 20
1. Temperature Display: The temperature of the case is displayed here. When the case is in defrost mode, this display will read DEF.
2. When lit, this icon indicates the compressor is running.
3. When lit, this icon indicates the fans are running.
4. When lit, this icon indicates the defrost heater is activated.
5. This icon ashes in an alarm situation.
6. Buttons:
a. Prg/mute: This button is used to silence the audible alarm. The alarm will re-energize after 60 minutes if the condition that caused it
has not been corrected. This button is also used to make basic changes to the program and should be used only by a qualied service
technician.
b. Set: This button is used to program the control and should be used only by a qualied service technician.
c. Up Arrow/aux: This button is used to program the control and should be used only by a qualied service technician.
d. Down Arrow/def: This button is used to program the control and should be used only by a qualied service technician.
Basic Case Operations
1. The case’s condensing unit (mounted on top of the case) cycles off and on during normal operation. When the inside of the case is warm,
the compressor turns on. When the inside of the case is cold, the compressor turns off.
2. On medium temp cases, the fans run all of the time. On low temp cases, the fans run when the evaporator temperature is below 30ºF,
except when in defrost.
3. The case goes into defrost two times per day. The defrost lasts between 30 and 50 minutes. At the end of the defrost, the low temp doors
may fog on the inside. This is normal. During the defrost, the air in the ducts can warm up to 40ºF for a medium temp case and 60ºF for a
low temp case. Product temperatures within the case will not rise above acceptable levels, however. Product in medium temp cases will
remain at or below 41ºF and product inside low temp cases will remain frozen.*
4. The lights remain on at all times unless the light switch located in the right-hand door frame is switched off.
5. The water removal system has a maximum capacity of two gallons. When cleaning the interior of the case, do not use more than this
amount of liquid.
*Please consult the Zero Zone Service Department on case defrost characteristics for non-standard defrost settings.
4 • Carel Controller - Basic Operations
CAREL CONTROLLER
Silencing the Temperature Alarm
Press [Prg] Button to
silence the alarm
The button used to silence the alarm ([Prg] button) is located on the controller on the front of the case above the right-hand door.
If the alarm sounds, push the [Prg] button which will reset the alarm and silence it for one hour.
Alarm Instruction Label
An instruction label for the
electronic control can be
found afxed to the ceiling
of each case inside the
right-hand door.
See "Manager’s
Emergency Guide"
at the end of this
manual.
Carel Controller - Silencing the Temperature Alarm • 5
CAREL CONTROLLER
Conditions that Trigger the Alarm
Your LOW TEMP case has two defrosts programmed per day, one at 8:00 AM and one at 8:00 PM. A typical defrost lasts one hour. Your
MEDIUM TEMP case has two defrosts programmed per day, one at 8:00 AM and one at 8:00 PM. If the alarm sounds during this time, please
allow an additional one-hour recovery time before calling for service.
If the alarm sounds outside of the above times, please review the following checklist. If you’ve checked all of these items and the case still does
not work properly, submit a service request.
Cases with electronic controls (a digital display cut into the shroud above the doors) have a one-hour delay after defrost. The controller has a
10ºF high alarm set point. The alarm will sound when the sensed temperature is at or above 10ºF for a period of 60 minutes. If the temperature
drops below 10ºF during this 60 minutes, the alarm timer will reset. If the case is in defrost, the electronic display will read “DEF”.
Common Things to Check
DEFROST AND ALARMS
1. Check the circuit breakers for the cases. Tripped circuit breakers will cut off the power to the cases and to the alarms.
2. Reach-in door LOW TEMP cases have a one-hour defrost. Check the following before you enter a service request.
Determine when the defrost cycle started (typically at 8:00 AM or 8:00 PM). Please wait one hour and double check case status
before calling for service.
The fans turn off during defrost and for a few minutes after defrost.
Has the case just been stocked? (Warm product will take 24 hours to cool down.)
Is the case heavily shopped? (Frequent door opening will warm the case.)
Do not block return air grills at the bottom of the low temp case.
3. Reach-in door MEDIUM TEMP cases also have a defrost time. Check the following before you enter a service request.
Medium temp fans run while in defrost and lights remain on.
Typically medium temp cases defrost at 8:00 AM and 8:00 PM.
Has the case just been stocked? (Warm product will take 24 hours to cool down.)
Is the case heavily shopped? (Frequent door opening will warm the case.)
6 • Carel Controller - Conditions that Trigger the Alarm
MANAGER’S EMERGENCY GUIDE
Hybrid™ Display Cases
MANAGER’S EMERGENCY GUIDE
Hybrid™ Display Cases
Zero Zone medium and low temp Hybrid™ display cases have a built-in alarm system to alert you of problems with the operation of the case.
In the event of a problem, an alarm will sound (a constant beeping noise) and the display will fl ash an error code. If this occurs:
1. Press and hold the “Prg” button on the display for 5 seconds to silence the alarm. The “Prg” button is in the upper left of the control.
Doing so will silence the alarm for 60 minutes.
2. Identify the alarm code displayed on the screen. The FOUR most common alarm codes are listed below:
E0 = case temperature probe error
§
E1 = defrost temperature probe error
§
HI = high temperature inside the display case
§
LO = low temperature inside the display case
§
DEF = case is in defrost (this is not an error code)
3. If the error code is an E0 or an E1, then proceed to step #4; a qualifi ed refrigeration technician is required to correct the situation. In the
event of a high temperature alarm (HI), there is a chance that there is a simple fi x for the problem:
a. Verify that a door is not accidentally held open. Sometimes products will fall off the shelves and prevent a door from fully closing.
b. Confi rm that the case was not recently stocked with product. Holding one of the doors open for an extended period of time (as is the
case when stocking) will raise the internal temperature and possibly set off the alarm.
c. Determine whether a defrost cycle has recently occurred. Following the defrost period, the case temperature may be warmer
than usual.
d. Make sure proper airfl ow is not compromised by debris covering the balloon guard located at the front of each condensing unit on the
top of each case behind the shroud. You will need to use a step ladder to check this. If possible, remove the item or debris blocking
the balloon guard. If you are unable to easily remove the item or debris, call your service provider.
Identifying and correcting any of these problems will return the case temperature to normal conditions.
4. If the source of the problem was not identifi ed in step #3, a service request should be directed to your service provider immediately.
This image shows the controller
at normal operation.
This image shows the controller during an alarm
condition. This is the high temperature alarm code