Condenser Fan Operation; Condenser Fan Speed Control; High Pressure Control; Low Pressure Control - Bard FUSION-TEC HR58APA Installation Support Materials

FIGURE 2.24
Adjusting Discharge Temperatue Input

Condenser Fan Operation

Condenser Fan Speed Control

The condenser fan motor maintains its high efficiency
across a wide operating range. The result is a
significant reduction in energy use when the motor is
run at reduced speeds. See Table 2.3.
TABLE 2.3
Condenser Fan Speeds
Mode Speed %
High Ambient 71 – 100
Low Ambient 25 – 71
Normal 71
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Controller
CFM
Output Volts
2726 –
7.1 v – 10.0 v
3703
1130 –
2.5 v – 7.1 v
2726
7.1 v 2726
FIGURE 2.29
Pressure Control

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 wll be disabled when the
discharge pressure reaches 620 PSI to reduce the
required condenser airflow.
High Pressure Cut Out
See chart in Figure 2.25.

Low Pressure Control

When the discharge pressure reaches 375 PSI, the
condenser fan will begin to slow down to attempt to
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.