Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
79
204 COND LOW AMB
(Only HVAC)
Standard condenser logic dictates that a newly started compressor will use its own discharge
pressure as the control for the first five minutes. If this Setpoint is active and the ambient
temperature sensor is reading less than the value of this Setpoint, then this compressor’s
discharge pressure will remain in control for the additional time in seconds as specified in
the ‘Time (sec)’ field.
206 COND HI AMB If active, standard condenser control on compressor startup logic will be bypassed when
there is a high ambient temperature. If the condenser type is common and the ambient
temperature is above the value of this Setpoint, then the compressor with the highest
discharge pressure will have control of the condenser.
7.74.3.4. No Condenser
This option indicates there is no condenser associated with this unit.
7.74.3.5. RO Step Common
The RO Step Common of condenser has one bank of fans. Make sure that all compressors in the Circuit Base point to
the same common fan bank. The above example does not have a Fan Analog Output and there are three stages of
fans starting with CND FAN 1 relay. All stages must be consecutive Relay Outputs.
For example:
Setpoint # Name Value
45 CND STG1 ON 200.0P
46 CND STG2 OFF 170.0P
47 CND DIFF ON 15.0P
48 CND DIFF OFF 5.0P
Discharge control pressure is 200.0 P, CND FAN 1, first condenser stage will be turned on.
If control pressure is equal to or greater than 215.0 P then the second stage will be turned on. (200.0 + (15.0 * 1))
If control pressure is equal to or greater than 230.0 P then the third stage will be turned on. (200.0 + (15.0 * 2))
Discharge control pressure is above 230.0 P; all three condenser stages are on.
When the control pressure drops below 180.0P the third condenser stage will be turned off. (170.0 + (5.0 * 2))
When the control pressure drops below 175.0P the second condenser stage will be turned off. (170.0 + (5.0 * 1))
When the control pressure drops below 170.0P the first condenser stage will be turned off. (170.0)
Condenser Faults
This example has no condenser faults. If used, and any one of the digital inputs are ON for the time specified in
Setpoint #90 if active, then the unit will be locked out and an alarm message will be generated.