Bryant 661G, 661S, 661C VII. Check Defrost Thermostat, VIII. Make Piping Connections

TABLE 1—REFRIGERANT CONNECTIONS AND RECOMMENDED LIQUID AND VAPOR TUBE DIAMETERS (IN.)

UNIT	LIQUID		VAPOR		VAPOR (LONG LINE)
SIZE	Connection Diameter	Tube Diameter	Connection Diameter	Tube Diameter	Connection Diameter	Tube Diameter
018, 024	3/8	3/8	5/8	5/8	5/8	3/4
060, 036	3/8	3/8	3/4	3/4	3/4	7/8
042, 048	3/8	3/8	7/8	7/8	7/8	1-1/8
060	3/8	3/8	7/8	1-1/8	7/8	1-1/8

NOTES:

1.Tube Diameters are for lengths up to 50 ft or 20 ft vertical differential. For tubing lengths greater than 50 ft, consult the Application Guideline and Service Manual for Air Conditioners and Heat Pumps Using R-22 Refrigerant.

CAUTION: Remove indoor coil piston if unit is to be installed on system with a TXV metering device.

Check outdoor unit piston. Remove retainer on liquid service valve and check piston size with matching number listed on outdoor unit rating plate.

VII. CHECK DEFROST THERMOSTAT

Check defrost thermostat to ensure it is properly located and securely attached. There is a liquid header with a brass distributor and feeder tube going into outdoor coil. At the end of 1 of the feeder tubes, there is a 3/8-in. O.D. stub tube approximately 2 in. long. (See Fig. 5.) The defrost thermostat should be located on stub tube. Note that there is only 1 stub tube used with liquid header, and on most units it is the bottom circuit.

FEEDER TUBE

STUB TUBE

DEFROST

THERMOSTAT

A97517

Fig. 5—Defrost Thermostat Location

VIII. MAKE PIPING CONNECTIONS

WARNING: Relieve pressure and recover all refrigerant before system repair or final unit disposal to avoid personal injury or death. Use all service ports and open all flow-control devices, including solenoid valves.

CAUTION: If ANY refrigerant tubing is buried, provide a 6 in. vertical rise at service valve. Refrigerant tubing lengths up to 36 in. may be buried without further special consideration. For lengths above 36 in., consult your local distributor.

—3—

CAUTION: To prevent damage to unit or service valves observe the following:

•Use a brazing shield.

•Wrap service valves with wet cloth or use a heat-sink material.

Outdoor units may be connected to indoor section using accessory tubing package or field-supplied refrigerant grade tubing of correct size and condition. For tubing requirements beyond 50 ft in length or 20 ft vertical differential, substantial capacity and performance losses can occur. Following the recommendations in the Residen- tial Split System Long-Line Application Guideline will reduce these losses. Refer to Table 1 for field tubing equivalent line length.

If refrigerant tubes or indoor coil are exposed to atmosphere, they must be evacuated to 500 microns to eliminate contamination and moisture in the system.

A.Outdoor Unit Connected to Factory-Approved In- door Unit

Outdoor unit contains correct system refrigerant charge for opera- tion with indoor unit of same size when connected by 15 ft of field-supplied or factory-accessory tubing. Check refrigerant charge for maximum efficiency.

B. Refrigerant Tubing

Connect tubing to fittings on outdoor unit vapor and liquid service valves. (See Table 1.) Use refrigerant grade tubing. Refer to appropriate section below for type of service valves installed on unit.

C. Sweat Connection

CAUTION: To avoid valve damage while brazing, ser- vice valves must be wrapped in a heat-sinking material such as a wet cloth.

Remove plastic retainer holding outdoor piston in liquid service valve and connect sweat/flare adapter provided to valve. (See Fig. 6.) Connect refrigerant tubing to fittings on outdoor unit vapor and liquid service valves. Service valves are closed from factory and ready for brazing. After wrapping service valve with a wet cloth, tubing set can be brazed to service valve using either silver bearing or non-silver bearing brazing material. Consult local code require- ments. Refrigerant tubing and indoor coil are now ready for leak testing. This check should include all field and factory joints.

D. Final Tubing Check

IMPORTANT: Check to be certain factory tubing on both indoor and outdoor unit has not shifted during shipment. Ensure tubes are not rubbing against each other or any sheet metal. Pay close attention to feeder tubes, making sure wire ties on feeder tubes are secure and tight.