Foster EPREM 1/2H, Service Manual

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Temperature Recovery Period
This period allows the unit to cool the load back to the
normal operating temperature range following defrost.
The internal air temperature may have risen out of
the normal temperature ranges during the defrost period due to the doors being opened for
loading/unloading or a slight transfer of warm air from the evaporator to the air temperature probe. During
the temperature recovery period, which is a fixed 5 minute period after the evaporator fans restart, the LCM
text display will change to show ‘Temp. Recovery’ with the time elapsed clock continuing. During the first
two minutes of the temperature recovery period the LED temperature display will only show the function
indicators, however for the final three minutes of the temperature recovery period the internal air
temperature will also be shown.
Normal Operating Mode
Five minutes after the evaporator fans have restarted the LCM text display will be extinguished and the unit
will enter the normal operating mode and defrost will be completed.
A defrost can be initiated manually if required. The procedure for this is detailed in the ‘User Functions’
section, but the defrost operation and display will be the same as for an automatic defrost. Should a
manual defrost be initiated the automatic defrost clock will be reset, and therefore subsequent defrosts will
follow at the normal time interval.
Alarms and Warnings
Door Opening Warning
Display shows door open warning. The controller siren sounds, but can be muted by pressing any button. The
display will continue until cancelled by shutting the door. If the door open warning is muted and the door is left open
the warning will eventually become a temperature related problem and then the appropriated alarm would be
generated. The door alarm will sound after the period determined from the ‘Door Stop’ plus the ‘Door Alarm’
parameters. This will occur if the ‘Door Switch’ parameter is set to ‘Yes’
High Temperature Alarm
This alarm occurs if the internal temperature rises above the set point plus the hysteresis value, plus the high alarm
temperature differential for the time determined by the alarm delay period. If this alarm occurs, the LCM display will
flash the above alarm message. The alarm siren will sound but can be muted for a period of one hour by pressing
any button. The LCM display will continue to flash throughout this alarm. The LED display will show the internal air
temperature and the function icons. If the temperature has not returned to within the operating limits after one hour
the alarm will resound for one minute. This process will continue until automatically cancelled by the system
returning to its normal operating temperatures.
Low Temperature Alarm
This alarm occurs if the internal temperature falls below the set point minus the low alarm temperature differential
for the time determined by the alarm delay period. If this alarm occurs, the LCM display will flash the above alarm
message. The alarm siren will sound but can be muted for a period of one hour by pressing any button. The LCM
display will continue to flash throughout this alarm. The LED display will show the internal air temperature and the
function icons. If the temperature has not returned to within the operating limits after one hour the alarm will
resound for one minute. This process will continue until automatically cancelled by the system returning to its
normal operating temperatures.
Air Temperature Probe Failure
The display will flash ‘Probe 1’, as shown above, indicating an air probe (T1) failure; it is not possible to display the
temperature with a probe 1 fault. The alarm will sound but can be temporarily muted by pressing any button. The
siren will resound after one hour for one minute if the fault has not been rectified. During this period the unit will
continue to operate, as determined by the ‘Comp.Cycle’ parameter, but will have a reduced performance as the
compressor ON and OFF function will be on a timed basis. It is not possible to view the air or food temperature
when this fault occurs. The alarm message will continue to be displayed until the fault has been rectified and then
cleared by entering the ‘Basic User Functions’ and deleting the alarm message.
Evaporator Temperature Probe Failure
The display will flash ‘Probe 2’, as shown above, indicating an evaporator probe (T2) failure. The alarm will sound
but can be temporarily muted by pressing any button. The siren will resound after one hour for one minute if the
fault has not been rectified. During this period the unit will continue to operate but this failure will have an effect on
the defrost, termination on a timed basis and not temperature, and therefore effect efficiency if unfixed, The alarm
message will continue to be displayed until the fault has been rectified and will then automatically reset and the unit
will function normally
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