Bryant 559F Start-Up, Unit Preparation, II. Service Valves, III. Internal Wiring, RETURN-AIR Fans

SENSOR	SENSOR
LOCATION	LOCATION

HAIRPIN END	HAIRPIN END
559F240	559F300

NOTE: All sensors are located on the eighth hairpin up from the bottom.

Fig. 24 Ð Motormaster III Sensor Locations

START-UP

Use the following information and Start-Up Checklist on page CL-1 to check out unit PRIOR to start-up.

I. UNIT PREPARATION

Check that unit has been installed in accordance with these installation instructions and all applicable codes.

II. SERVICE VALVES

Ensure that optional suction, discharge, and standard liquid line service valves are open. Damage to the compressor could result if they are left closed.

III. INTERNAL WIRING

Check all electrical connections in unit control boxes; tighten as required.

IV. CRANKCASE HEATER(S)

Heater(s) is energized as long as there is power to unit and compressor is operating.

IMPORTANT: Unit power must be on for 24 hours prior to start-up. Otherwise, damage to compressor may result.

V. COMPRESSOR MOUNTING

Compressors are internally spring mounted. Do not loosen or remove compressor holddown bolts.

VI. REFRIGERANT SERVICE PORTS

Each refrigerant system has a total of 3 Schrader-type serv- ice gage ports. One port is located on the suction line, one on the compressor discharge line, and one on the liquid line. In

addition, Schrader-type valves are located underneath the low- pressure switches. Be sure that caps on the ports are tight.

VII. COMPRESSOR ROTATION

It is important to be certain the compressors are rotating in the proper direction. To determine whether or not compres- sors are rotating in the proper direction:

1.Connect service gages to suction and discharge pres- sure ®ttings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pres- sure should rise, as is normal on any start-up.

If the suction pressure does not drop and the discharge pres- sure does not rise to normal levels:

1.Note that the evaporator fan is probably also rotating in the wrong direction.

2.Turn off power to the unit.

3.Reverse any two of the incoming power leads.

4.Turn on power to the compressor.

The suction and discharge pressure levels should now move to their normal start-up levels.

NOTE: When compressors are rotating in the wrong direc- tion, the unit will have increased noise levels and will not provide heating and cooling.

After a few minutes of reverse operation, the scroll compres- sor internal overload protection will open, which will acti- vate the unit's lockout and requires a manual reset. Reset is accomplished by turning the thermostat on and off.

VIII. EVAPORATOR FAN

Fan belt and variable pulleys are factory installed. Remove tape from the fan pulley. See Table 4 for Air Quantity Limits. See Tables 5-7 for Fan Performance data. Be sure that fans rotate in the proper direction. See Tables 8 and 9 for Static Pressure information for accessories and options. See Table 10 for fan rpm at various fan motor pulley settings. To alter fan performance, see Evaporator-Fan Performance Ad- justment section, page 21.

Table 4 Ð Air Quantity Limits

UNIT 559F	MINIMUM CFM	MAXIMUM CFM
180	4500	7,500
216	5400	9,000
240	6000	10,000
300	7000	11,250

IX. CONDENSER FANS AND MOTORS

Fans and motors are factory set. Refer to Condenser-Fan Ad- justment section (page 22) as required.

X. RETURN-AIR FANS

Check that correct ®lters are installed in ®lter tracks. See Table 1. Do not operate unit without return-air ®lters.

XI. OUTDOOR-AIR INLET SCREENS

Outdoor-air inlet screens must be in place before operating unit.

XII. ACCESSORY ECONOMIZER ADJUSTMENT

Remove ®lter access panel. Check that outdoor-air damper is closed and return-air damper is open.

Economizer operation and adjustment is described in Base Unit Operation and Economizer Adjustment sections (pages 20 and 22), respectively.

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