Manual 2100-670
Page
20 of 32
Mode
Speed %
Controller
Output Volts
CFM
High Ambient
71 – 100
7.1 v – 10.0 v
2726 –
3703
Low Ambient
25 – 71
2.5 v – 7.1 v
1130 –
2726
Normal
71
7.1 v
2726
TABLE 8
Condenser Fan Speeds
High Pressure Control
Condenser Fan Speed
When the discharge pressure reaches 590 PSI, the
condenser fan will begin to speed up to attempt to
bring the pressure back down. The speed will continue
to ramp up until the discharge pressure reaches 630
PSI. At this point, the fan will be operating at full
speed, moving as much air as possible.
Second Stage Drop Out
The second stage of cooling will be disabled when the
discharge pressure reaches 620 PSI to reduce the
required condenser airflow.
High Pressure Cut Out
See chart in Figure 26.
Low Pressure Control
When the discharge pressure reaches 375 PSI, the
condenser fan will begin to slow down to attempt to
FIGURE 26
Pressure Control
bring the pressure back up. The speed will continue
to ramp down until the discharge pressure reaches
340 PSI. At this point, the fan will be operating at
minimum speed, moving as little air as possible.
If the discharge pressure continues to go down to
250 PSI, the condenser fan will turn off. The fan
will remain off with the compressor running until the
pressure reaches 340 PSI. The fan will then turn back
on at the minimum speed. The fan will continue to run
at the minimum speed until the pressure drops again or
starts to rise above the 340 PSI setpoint and begins to
speed up again.
Additional Condenser Fan Alarms
Dirty Condenser Coil Alarm
The unit will continuously monitor system conditions
to determine if the condenser coil is dirty or blocked.
If the system monitors three consecutive cooling
cycles that indicate a dirty condenser coil, an alarm
will be generated. This alarm is a notification and will
automatically reset when conditions are no longer
present. The end user has the ability to adjust how
dirty the coil gets before an alarm is generated and how
many consecutive cycles before the alarm is triggered.
To change these settings:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
TECHNICIAN password 1313.
3. Press UP or DOWN keys to scroll to
Adv System
Config
; press ENTER key.
4. Press UP or DOWN keys to scroll to
Dirty Cond
Alarm (B4)
; press ENTER key.
