Staging; Dehumidification; Electronic Expansion Valve (Eev); Eev Components - Bard FUSION-TEC HR35BPA Service Instructions Manual

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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 22).
FIGURE 22
Viewing Unit Stages

Dehumidification

The unit uses a dehumidification sequence that does
not require the electric heat to run at the same time
as the compressor. Instead, the unit will turn on the
compressor to cool down to the heating setpoint.
Once the lower setpoint has been reached, the unit
will heat the space back up to the upper setpoint.
This cycle continues until the humidity level in the
shelter reaches an acceptable level. At this point,
the unit will revert back to normal operation. The
economizer will also be disabled while the unit is in
the dehumidification mode.
NOTE: This feature is dependent upon the LV1000
indoor humidity sensors and a command
from the LV to enter dehumidification mode.
See the latest revision of LV1000 Service
Instructions 2100-673 for adjustment of the
dehumidification setpoint and differentials.
Manual 2100-694B
Page
16 of 62

Electronic Expansion Valve (EEV)

EEV Components

Electronic Expansion Valve

The electronic expansion valve is a stepper motor that
is controlled with a step output from the controller. The
valve is capable of 480 steps represented by a 0-100%
signal on the controller. The motor drives a needle valve
that regulates the flow of refrigerant.

EEV Instructions for Vacuum, Reclaim, Charge Unit

The electronic expansion valve moves to the 40% open
position when the unit is not actively cooling. The
valve may need to be manually positioned for service or
troubleshooting. The valve can be positioned by using a
menu override.
To manually override the valve:
NOTE: The unit must be off to perform this override.
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 I/O Config;
press ENTER key.
4. Press UP or DOWN keys to scroll to EEV Service
C15; press ENTER key.
5. Press ENTER key to scroll to Enable (see Figure 23).
6. Press UP or DOWN key to change Disable to Enable.
7. Press ENTER key to scroll to Position.
8. Press UP or DOWN keys to adjust to the desired
value.
9. Press ENTER key to save.
FIGURE 23
Overriding EEV Output
The valve can also be opened or closed using the EEV
service tool (Bard Part # 2151-021). This magnetic
EEV service tool (shown in Figure 24) is used to
manually open the EEV. To do this, remove the EEV
stator coil (red color with retaining nut on top), slide
the magnetic tool over the shaft where the stator was
removed and turn in a clockwise direction to open the
valve to the full open position (directional arrows are

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