CVH8, HVH8, TVH8, VA9, HVA9, TVA9: APPLICATION GUIDELINE & SERVICE MANUAL
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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Aluminum Wire
Whenever aluminum wire is used in branch circuit wiring with this unit,
adhere to the following recommendations.
Connections must be made in accordance with the National Electrical
Code (NEC), using connectors approved for aluminum wire. The
connectors must be UL approved (marked Al/Cu with the UL symbol)
for the application and wire size. The wire size selected must have a
current capacity not less than that of the copper wire specified, and must
not create a voltage drop between service panel and unit in excess of 2 of
unit rated voltage. To prepare wire before installing connector, all
aluminum wire must be “brush-scratched” and coated with a corrosion
inhibitor such as Pentrox A. When it is suspected that connection will be
exposed to moisture, it is very important to cover entire connection
completely to prevent an electrochemical action that will cause
connection to fail very quickly. Do not reduce effective size of wire,
such as cutting off strands so that wire will fit a connector. Proper size
connectors should be used. Check all factory and field electrical
connections for tightness. This should also be done after unit has reached
operating temperatures, especially if aluminum conductors are used.
Unit Electrical Power
Power wires from the unit’s disconnect should be routed through the
power wiring hole provided at the bottom of the unit’s control box.
Connect the ground wire to the ground connection in the control box and
connect the power wiring to the terminal block as shown on the wiring
and Installation Instructions supplied with the unit. The unit does not
require a contactor or outdoor unit transformer in order to operate.
MAJOR COMPONENTS
Application Operational Control Board (AOC)
A160120
Fig. 1 – AOC (Application Operational Control) Board
The AOC board is located in the lower right hand side of inverter tray.
It’s functions include:
• Compressor speed control
• Outdoor fan motor control
• Reversing valve operation
• Defrost operation
• Crankcase heater operation
• Pressure switch monitoring
• Time Delays
• Pressure Transducer measurements
• PEV control (pressure equalizer valve)
• Temperature measurements
• EXV (Electronic Expansion Valve) operation control
• Inverter communication and control
CAUTION
!
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this caution may result in equipment damage or
improper operation.
Aluminum wire may be used in the branch circuit (such as the circuit
between the main and unit disconnect), but only copper wire may be
used between the unit disconnect and the unit.
