IMPORTANT: THE VAV (variable air volume) units use variable frequency drives, which generate, use and can radiate radio frequency energy. If units are not in- stalled and used in accordance with these instructions, they may cause radio interference. They have been tested and found to comply with limits of a Class A com- puting device as de®ned by FCC (Federal Communi- cations Commission) regulations, Subpart J of Part 15, which are designed to provide reasonable protection against such interference when operated in a commer- cial environment.
The unit must be electrically grounded in accordance with local codes and NEC ANSI/NFPA 70 (National Fire Protection Association).
Affix crankcase heater sticker (located in the installers packet) to unit disconnect switch.
Voltage to compressor terminals during compressor op- eration must be within the voltage range indicated on the unit nameplate. On
On
1.Remove cap from red (208 v) wire.
2.Remove cap from spliced orange (230 v) wire. Discon- nect orange wire from black unit power wire.
3.Cap orange wire.
4.Splice red wire and black unit power wire. Cap wires.
IMPORTANT: BE CERTAIN UNUSED WIRES ARE CAPPED. Failure to do so may damage the transformers.
FIELD CONTROL WIRING Ð The unit can use either a
Thermostat Wiring (CV Only) Ð Install a
Route the thermostat cable or equivalent single leads of colored wire from the subbase terminals to the
NOTE: For wire runs up to 50 ft, use no. 18 AWG (American Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft, use no. 16 AWG insulated wire (35 C minimum). For over 75 ft, use no. 14 AWG insulated wire (35 C mini- mum). All wire larger than no. 18 AWG cannot be directly connected at the thermostat and will require a junction box and splice at the thermostat.
Set heat anticipators to 0.1 for all voltages.
Sensor Wiring (CV or VAV) Ð The temperature sensor is wired into the unit control board. See Fig. 21.
The unit is controlled with a
If more than sensor is being used and averaged, sensors must be wired in multiples of 4 or 9. See Fig. 22.
Heat Interlock Relay Ð VAV units require a
| LEGEND |
GND Ð Ground | |
NEC | Ð National Electrical Code |
TB | Ð Terminal Block |
NOTE: Maximum wire size for TB1 is 500 MCM.
Fig. 17 Ð Field Power Wiring Connections
|
| LEGEND |
|
| |
C | Ð | Compressor/Contactor | IF | Ð | Indoor Fan |
CB | Ð Circuit Breaker | OF | Ð Outdoor Fan | ||
DIP | Ð | Dual | PEC | Ð | Power Exhaust Controller |
FU | Ð | Fuse | TB | Ð | Terminal Block |
HR | Ð | Heater Relay | TRAN Ð | Transformer |
Fig. 18 Ð Control Box Diagram (Sizes 024-034)
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