Heating; Electronic Expansion Valve (Eev); Eev Components; Electronic Expansion Valve - Bard MEGA-TEC W090A Service Instructions Manual

Compressor 1 Stage 2
Compressor 2
Compressor 1 Stage 1
75.0°F 75.5°F 76.0°F 76.5°F 77.0°F 77.5°F 78.0°F 78.5°F 79.0°F 79.5°F 80.0°F 80.5°F 81.0°F
Electric Heater 2
Electric Heater 1

Heating

The unit can be equipped with 0, 1 or 2 stages of
electric heat (see Figure 16).

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 20% 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.
FIGURE 15
Cooling (without Economizer)
Off
FIGURE 16
Heating
58.0°F 58.5°F 59.0°F
Heating
Cooling Deadband Cooling
59.5°F 60.0°F 60.5°F
Heating Deadband
3. Press UP or DOWN keys to scroll to I/O Config;
press ENTER key.
4. Press UP or DOWN keys to scroll to Manual EEV;
press ENTER key.
5. Press UP or DOWN keys to scroll to EEV Circuit 1
or EEV Circuit 2.
6. Press ENTER key to scroll to Service Pos (see
Figure 17).
Overriding EEV Output
7. Press UP or DOWN keys to adjust to the desired
value.
61.0°F 61.5°F 62.0°F
Off
FIGURE 17
Manual 2100-671C
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