Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
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7.74.3.10. RO Shared
The RO Shared condenser has banks of fans that are shared between two consecutive circuits. The number and
location of the fans are specified under the Circuit Base screen. This is similar to the RO Step Individual set up.
Circuits 1 and 2 will share the fan bank that is specified in the circuit 1 grid in the Circuit Base screen. The highest
discharge pressure of these two compressors will be used to control this bank of fans. Circuits 2 and 3 will share the
fan bank that is specified in the circuit 2 grid in the Circuit Base screen. The highest discharge pressure of these two
compressors will be used to control this bank of fans. In a unit with three circuits, circuit three will not have a fan bank
associated with it. It shares circuit 2’s fan bank.
7.74.3.11. Dual V8
This is a special type of condenser. It is a common circuit control type with two stages of fans and VFD. The control of
the fan speed will be different depending on whether one or two stages are on. All circuits are checked to calculate the
control discharge pressure, and should be in the same fan bank.
If the control discharge pressure is less than Setpoint #45, then both condenser stages are off and the fan speed is
zero.
If the control discharge pressure is greater than Setpoint #45 and less than Setpoint #46 stage 1 will be on. The fan
speed will be equal the value of (Setpoint #55 minus Setpoint #54) divided by (Setpoint #46 minus Setpoint #45) and
then multiplied by (control discharge pressure minus Setpoint #46) plus Setpoint #54.
If the control discharge pressure increases while in stage 1 above the value of Setpoint #46 plus Setpoint #48 for the
time contain in Setpoint #49 stage 2 will be entered. Both relays will be on and the fan speed will be equal the value of
(Setpoint #55 minus Setpoint #54) divided by Setpoint #46 and then multiplied by (control discharge pressure minus
Setpoint #46) plus Setpoint #54.
If the speed of the condenser fan is less than Setpoint #54 it will be set to that value or if the speed of the condenser
fan is greater than Setpoint #55 it will be set to that value.