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The wiring diagram in the evaporator will indicate field interface terminals to the secondary heat
ex- changer. The internal wiring of the secondary heat exchanger is found on a separate diagram
which can be found on the inside cover of the heat exchanger electrical box. Both diagram types
are also placed inside the shipping/warranty packet secured in the evaporator section.
3.19. Electronic Expansion Valve
The Electronic Expansion Valve (EEV) is standard for this unit. This high efficiency feature
provides an EEV in place of the standard Thermal Expansion Valve (EEV). The EEV controls
superheat through the dap4 controls by actively measuring suction pressure via a transducer
attached to the suction line and suction temperature via a thermal transducer strapped to the
suction line. The EEV actively adjusts the orifice size and resulting mass flow of refrigerant to
maintain the superheat setpoint. The EEV maintains more stable system balance and is more
energy efficient. With variable capacity systems, an electronic expansion valve is the solution
to handle refrigerant mass flow variations.
3.19.1. Electrical Connection to EEV
The Electric Expansion Valve (EEV) uses an electrical cable assembly with a DIN type connector
to interface with EEV valve stator. The connector is indexed by one large blade connection so
that the connector can only properly mate one way. When it is necessary to make this electrical
connection, this connector can only properly mate in one position as shown in the picture below.
Figure 13 EEV with Electrical Mating Connector
WARNING:
DO NOT
try to mate this connector in any other direction or
attempt to use excessive force to make the electrical connection