Alarm For Low Difference Between High And Low Pressure; Low Superheating Alarm - Daikin UATYA-B Operation Manual

4.4.4 Alarm for low difference between high and low pressure
Checking of the difference between high and low pressure values takes place when at least one compressor of the circuit
involved is running.
Upon compressor start-up, a certain difference must be generated between high and low pressure in order to ensure correct
compressor rotation and oil return to the compressor.
The parameters involved are shown in the table.
The values of the parameters are representative. In specific cases, different values can be set.
Parameter Value
PAL92 3.00
PAL93 60
PAL94 90
PAL95 2
Alarm code
Reason for activation
Reset mode
Alarm icon
AlarmLog
Alarm relay
Devices
Compressors
The other devices
4.4.5 Low superheating alarm
Where an electronic expansion valve is fitted, the controller manages the superheating of the intake gas to the compressor.
The parameters involved are shown in the table.
The values of the parameters are representative. In specific cases, different values can be set.
Parameter Value
Et30 300
Et37 2.0
PAL4 5
Alarm code
Reason for activation
Reset
Reset mode
Alarm icon
AlarmLog
Alarm relay
Devices
Compressors
The other devices
Daikin R32 Rooftops UATYA-B
ESIE21-02 – 2021.03
UM Description
bar Low pressure difference alarm threshold
s Low pressure difference alarm delay on starting of compressors
s Low pressure difference alarm delay at steady state
- Maximum number of alarms in one hour due to low pressure difference
AL114 for circuit 1; AL115 for circuit 2
Upon start-up of one compressor in the circuit, if the pressure difference is <= than PAL92
for the number of seconds set in PAL93
After the time in PAL93 has elapsed, if the pressure difference is <= than PAL92 for the
seconds set in PAL94
Automatic; switches to manual after the trip occurrences per hour set in "PAL95"
Flashing
Yes
Based on "alarm.conf" file
Behaviour in the event of an alarm
Only the compressors of the circuit involved are switched off
They follow their control
UM Description
s Low superheating alarm delay
°C Low superheating protection threshold
- Maximum number of alarms in one hour due to low pressure
AL170 for circuit 1; AL171 for circuit 2
If the measured superheating value is lower than threshold ET37 for a time longer than the
setpoint in parameter ET30
When the measured superheating value is higher than or equal to threshold ET37 +1°C for
1 second
Automatic until the number of trip occurrences in one hour set in parameter PAL4 is rea-
ched
Manual as soon as the number of trip occurrences in one hour set in parameter PAL4 is
exceeded
Flashing
Yes
Based on "alarm.conf" file
Behaviour in the event of an alarm
Only the compressors of the circuit involved are switched off
They follow their control
4 Alarms
Service manual
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