Temperature/Humidity Control Operation; Cooling; Heating; Staging - Bard FUSION-TEC HR58APA Installation Support Materials

Temperature/Humidity Control Operation

The unit utilizes a PID control loop for space control.
This control will compare the space temperature to
the space setpoint. Based on how far away from the
setpoint the temperature is, the loop will output a
cooling or heating capacity number between 0 and
100%. The unit will then take all of the available
cooling methods and distribute them evenly across the
0-100% range. The stages are then brought on as the
heating or cooling capacity reaches the percentage that
brings the stages on or off. There are separate setpoints
for cooling and heating.
To change or view the unit setpoint:
1. From the Status screen, press UP or DOWN key
until Quick Menu displays Setpoints icon (
Press ENTER key.
2. Press ENTER key to scroll to Local Cool or Local
Heat (see Figure 2.6).
3. Press UP or DOWN keys to change the value to
desired heating and/or cooling setpoint.
FIGURE 2.6
Setpoints
Freecooling
Compressor Stage 1
Compressor Stage 2
-10%
Deadband (sometimes called a neutral zone or dead zone) is an interval of a signal domain or
band where no action occurs
).
FIGURE 2.7
Cooling w/Economizer
0% 10% 20% 30% 40%
Off

Cooling

The unit is equipped with 1 stage of freecooling and
2 stages of mechanical cooling (compressor and
unloader) for a total of 3 cooling stages (see Figure
2.7).
The unit is equipped with 1 stage of freecooling and
2 stages of mechanical cooling (compressor and
unloader). However, the outdoor conditions are not
favorable for economizer operation so there are a total
of 2 cooling stages (see Figure 2.8 on page 30).

Heating

The unit is equipped with 1 stage of electric heat (see
Figure 2.9 on page 30).

Staging

The unit will stage the cooling components based on
the cooling demand referenced in the temperature
control. The unit will stage the economizer on first if
the indoor and outdoor conditions are favorable. The
compressor stage 1 will be enabled next as the demand
increases. Finally, the compressor stage 2 will be
enabled as the demand continues to increase.
The unit is only equipped with one stage of heat and
will turn on based on the heating demand.
To view unit stages:
1. From the Status screen, press UP or DOWN key
until Quick Menu displays Unit Information icon
( ). Press ENTER key.
2. The cooling and heating demand are visible on
this screen. The unit stages will display here when
active as FC, CL1, CL2 or H1 (see Figure 2.10 on
page 30).
50% 60% 70% 80%
Deadband On
90% 100% 110% 120%
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