Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
151
# Name Description
98 LLS#2 ON This Setpoint is used to control a second liquid line solenoid. When the actual circuit capacity
is greater than this value (can either be number of steps for Fixed Step compressors, or
percentage of full load amps for Variable Step compressors) for the number of seconds
in the ‘Time (sec)’ field, the second liquid line solenoid will open. When the actual circuit
capacity falls below this value minus the ‘Lockout Delay Hrs.’ Field, then the second
liquid line will be turned off.
‘Time (sec)’ field: The delay in seconds before the solenoid will be turned on. If zero, then
there will be no delay.
‘Lockout Delay Hrs.’ Field: Offset that will be subtracted from the value of this Setpoint. When
the actual circuit capacity falls below this offset, the solenoid will be turned off. If zero,
then an offset of 20% will be used.
99 LLS#3 ON
(ECONOMIZER)
This Setpoint is used to control a third liquid line solenoid. When the actual circuit capacity is
greater than this value (can either be number of steps for Fixed Step compressors, or
percentage of full load amps for Variable Step compressors) for the number of seconds
in the ‘Time (sec)’ field, the third liquid line solenoid will open. When the actual circuit
capacity falls below this value minus the ‘Lockout Delay Hrs.’ Field, then the third liquid
line will be turned off.
‘Time (sec)’ field: The delay in seconds before the solenoid will be turned on. If zero, then
there will be no delay.
‘Lockout Delay Hrs.’ Field: Offset that will be subtracted from the value of this Setpoint. When
the actual circuit capacity falls below this offset, the solenoid will be turned off. If zero,
then an offset of 20% will be used.
If the LO DISC SHEAT Setpoint #84 is active and the discharge superheat goes below the
value in this Setpoint for the safety time / 9, the economizer will be turned off.
100 HIGH SUMP TEMP If active, and sump temperature is above the value of this Setpoint for the time specified, a
HIGH SUMP TEMP alarm is generated and the unit is locked out.
101 SAFETY HOLD
DELAY
Time in seconds that the circuit will remain in a hold state after the condition that caused it
has returned to normal. The circuit can be holding for the following reasons:
 Low suction pressure
 Low refrigerant temperature
 High discharge pressure
 High discharge temperature
 High amperage
102 PUMP FREEZE
PROTECTION
If active, and the leaving temperature sensor is below the value of this Setpoint, a pump will
be forced on to protect against freezing. The leaving temperature must rise above this
Setpoint plus Setpoint #192 “FRZ TMP DIFF” to turn the pump off again.
103 LEAD COMP Enables the user to specify the lead compressor. The value of this Setpoint will indicate the
lead compressor. If zero, then auto rotation is enabled.
‘Time (sec)’ field: If non-zero, the compressor with the least amount of run time will be made
the lead upon rotation.
104 COMP ROTATION Specifies the number of days between rotations (Setpoint #103 must be set to zero to enable
auto rotation). If zero, then rotation will occur with every cycle.
105 PUMP FAILURE
(NO FLOW)
If active, flow is lost, and only one pump is present, then the system will be locked out. If the
system has two pumps and flow is lost, then the backup pump will start and the lead
pump will be locked out. If the second pump is running and flow is lost again then the
entire system will be locked out. A lock out reset will be required to restart the system or
to reactivate a locked out pump.
If inactive, and the flow is lost, the system will move to the OFF- NO EVAP FLOW state.
When flow is returned the system will automatically restart.
If looking at individual pumps for each circuit in the Circuit base. Make this Setpoint a
"Lockout". If flow is not made within the value of this Setpoint the first time than, an alarm
will be generated. The system counts through the value of this Setpoint a second time, if
flow is made then the unit will run as normal. If flow is not made the second time, the
pump and all associated compressors for that circuit will be locked out.