Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
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2) Control sensor reading is above the control zone but the Rate of Change is less than the value in
the (MAX ROC-, #27) Setpoint. This indicates that the temperature is decreasing toward the
target at an acceptable speed. Therefore, no additional cooling is needed at this time.
3) The temperature is below the control zone but the Rate of Change is greater than the (MAX
ROC+, #28) Setpoint. This indicates that the temperature is increasing toward the target.
Therefore, no reduction in cooling is needed at this time.
This state indicates that there is no need to adjust the capacity of the chiller package. This state will end
when more or less capacity is required.
UNIT UNLOADING (6) Only HVAC software 6.1.6.
This state is entered when less capacity is required. Every second an adjustment is made to the step
delay. When the delay reaches zero, the counter “steps wanted” on is decreased by 1.
UNIT UNLDNG-VANE (6) Only CENT software 6.1.7.
This state is entered when less capacity is required and the vanes are not completely closed. The close
vane relay will be modulated. The compressor speed will not be reduced in this state. Control temperature
can be below the control zone, or in the zone but the temperature is dropping too fast.
UNIT IS LOADING (7) Only HVAC software 6.1.8.
This state is entered when more capacity is required. Every second an adjustment is made to the step
delay. When the delay reaches zero, the counter “steps wanted on” is increased by 1.
UNIT IS LOADNG-VANE (7) Only CENT software 6.1.9.
This state is entered when more capacity is required (control temperature above control zone) and the
vanes are not 100% open. The open vane relay will be modulated. The compressor speed will not be
changed in this state.
OFF-SMOKE ALARM (8) 6.1.10.
This state is entered when a smoke alarm has been detected. In the MCS-Configuration file the Smoke
Alarm Indicator must be selected in the General Information panel under the MAG V8 screen. When this
sensor is trips, an error message “OFF-SMOKE ALARM” is generated and the unit state is changed. In
this state all RO’s except ALARM and OIL HEATER are turned OFF.
RUN/STOP SW OFF (9) 6.1.11.
This state is entered when the run stop switch is off, in the stop position. When the chiller is in this state,
the individual compressor states if active are moved to the CMP IS OFF state through the normal states.
One capacity STEP will be moved per second.
SCHEDULED OFF (10) 6.1.12.
This state is entered when the schedule is calling for the package to be off. When the chiller is in this
state, the individual compressor states if active are moved to the CMP IS OFF state through the normal
states. One capacity STEP will be moved per second.
OFF- NO FLOW (11) 6.1.13.
This state is entered when the evaporator flow switch is off. When the chiller is in this state, the individual
compressor states if active are moved to the CMP IS OFF state through the normal states. One capacity