Bryant 664B Install Electrical Connections, Minimum Airflow for Safe Electric Heater Operation

664B

Table 2 – Minimum Airflow for Safe Electric Heater Operation

Unit Size		Minimum Airflow (CFM)
	5kW	7.5kW	10kW	15kW	20kW
024	500	650	750	--	--
030	600	800	1050	--	--
036	600	800	1050	1150	1200
042	600	800	1050	1150	1200
048	600	800	1050	1150	1200
060	600	800	1050	1150	1200

Step 7 — Install Electrical Connections

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

The unit cabinet must have an uninterrupted, unbroken electrical ground to minimize the possibility of personal injury if an electrical fault should occur. This ground may consist of an electrical wire connected to the unit ground screw in the control compartment, or conduit approved for electrical ground when installed in accordance with NEC, ANSI/NFPA 70 American National Standards Institute/ National Fire Protection Association (latest edition) (in Canada, Canadian Electrical Code CSA C22.1) and local electrical codes.

!CAUTION

UNIT COMPONENT DAMAGE HAZARD

Failure to follow this caution may result in damage to the unit being installed.

1.Make all electrical connections in accordance with NEC ANSI/NFPA 70 (latest edition) and local electrical codes governing such wiring. In Canada, all electrical connections must be in accordance with CSA standard C22.1 Canadian Electrical Code Part 1 and applicable local codes. Refer to unit wiring diagram.

2.Use only copper conductor for connections between field-supplied electrical disconnect switch and unit. DO NOT USE ALUMINUM WIRE.

3.Be sure that high-voltage power to unit is within operating voltage range indicated on unit rating plate. On 3-phase units, ensure phases are balanced within 2 percent. Consult local power company for correction of improper voltage and/or phase imbalance.

4.Do not damage internal components when drilling through any panel to mount electrical hardware, conduit, etc.

HIGH-VOLTAGE CONNECTIONS

The unit must have a separate electrical service with a field-supplied, waterproof disconnect switch mounted at, or within sight from the unit. Refer to the unit rating plate, NEC and local codes for maximum fuse/circuit breaker size and minimum circuit amps (ampacity) for wire sizing.

The field-supplied disconnect may be mounted on the unit over the high-voltage inlet hole when the standard power and low-voltage entry points are used. See Fig. 6 and 7 for acceptable location.

Operation of unit on improper line voltage constitutes abuse and may cause unit damage that could affect warranty.

ROUTING POWER LEADS INTO UNIT

Use only copper wire between disconnect and unit. The high-voltage leads should be in a conduit until they enter the unit; conduit termination at the unit must be watertight. Run the high-voltage leads through the hole on the control box side of the unit (See Fig. 7). When the leads are inside the unit, run leads to the control box (See Fig. 8). For single-phase units, connect leads to the black and yellow wires (See Fig. 9).

CONNECTING GROUND LEAD TO UNIT GROUND

Connect the ground lead to the chassis using the unit ground in the control box (See Fig. 8 and 9).

ROUTING CONTROL POWER WIRES (24-V)

Form a drip-loop with the thermostat leads before routing them into the unit. Route the thermostat leads through grommeted hole provided in unit into unit control box (See Fig. 7). Connect thermostat leads and unit power leads as shown in Fig. 9, 10 and 11.

Route thermostat wires through grommet providing a drip-loop at the panel. Connect low-voltage leads to the thermostat as shown in Fig. 10 & 11.

The unit transformer supplies 24-v power for complete system including accessory electrical heater. Transformer is factory wired for 230-v operation.

ACCESSORY ELECTRIC HEAT WIRING

Refer to accessory electric heat installation instructions for information on installing accessory electric heat. Accessory electric heat wiring is shown in Fig. 17 and 18.

HIGH-VOLTAGE POWER	LOW-VOLTAGE WIRING
WIRING ENTRY HOLE		ENTRY HOLE
		(grommet hole)

A08407

Fig. 7 - Unit Electrical Connection

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