Bard WH483, WH602, WH421 Wiring Main Power, Wiring LOW Voltage Wiring, Unit 24V Terminal Board

WIRING — MAIN POWER

Refer to the unit rating plate for wire sizing information and maximum fuse or “HACR" type circuit breaker size. Each outdoor unit is marked with a “Minimum Circuit Ampacity”. This means that the field wiring used must be sized to carry that amount of current. Depending on the installed KW of electric heat, there may be two field power circuits required. If this is the case, the unit serial plate will so indicate. All models are suitable only for connection with copper wire. Each unit and/or wiring diagram will be marked “Use Copper Conductors Only”. These instructions must be adhered to. Refer to the National Electrical Code (NEC) for complete current carrying capacity data on the various insulation grades of wiring material. All wiring must conform to NEC and all local codes.

The electrical data lists fuse and wire sizes (75ºC copper) for all models, including the most commonly used heater sizes. Also shown are the number of field power circuits required for the various models with heaters.

The unit rating plate lists a “Maximum Time Delay Relay Fuse” or “HACR" type circuit breaker that is to be used with the equipment. The correct size must be used for proper circuit protection and also to assure that there will be no nuisance tripping due to the momentary high starting current of the compressor motor.

The disconnect access door on this unit may be locked to prevent unauthorized access to the disconnect. To convert for the locking capability, bend the tab located in the bottom left hand corner of the disconnect opening under the disconnect access panel straight out. This tab will now line up with the slot in the door. When shut, a padlock may be placed through the hole in the tab preventing entry.

See Start-up section for information on three phase scroll compressor start-ups.

NOTE:The voltage should be measured at the field power connection point in the unit and while the unit is operating at full load (maximum amperage operating condition).

Nine (9) wires should be run from thermostat subbase to the 24V terminal board in the unit. A nine conductor, 18 gauge copper, color-coded thermostat cable is recommended. The connection points are shown in Figure 7.

FIGURE 7

UNIT 24V TERMINAL BOARD

See Note 1

MIS-440

FACTORY JUMPER

IMPORTANT

Only the thermostat and subbase combinations as shown at the right will work with this equipment. The thermostat and subbase must be matched and the correct operation can be assured only by proper selection and application of these parts.

WIRING — LOW VOLTAGE WIRING

230/208V, 1 phase and 3 phase equipment dual primary voltage transformers. All equipment leaves the factory wired on 240V tap. For 208V operation, reconnect from 240V to 208V tap. The acceptable operating voltage range for the

240 and 208V taps are:

TapRange

240253 - 216

208220 - 187

Note 1: 1F93-380 thermostat must be set to "Heat Pump" mode to operate properly.

Press the program"RUN" button to make sure the thermostat is in run program model.

Press time "FWD" and "BACK" at the same time to enter User Configuration Menu.

Press and hold set "TIME" and "DAY" for about 3 seconds to enter Installer Menu.

The thermostat will display "MULTI STG"

Press the "UP" or "DOWN" button until the display reads "HEAT PUMP"

Press program "RUN" button to resume operation.

Manual 2100-399 Page 11