Bryant 663C → VII. Check Outdoor CHECK-FLO-RATER Piston, → VIII. Check Defrost Thermostat

COIL

SENSING

BULB

EQUALIZER

TUBE

THERMOSTATIC

EXPANSION

VALVE

A88382

Fig. 4ÐTypical TXV Installation

→VII. CHECK OUTDOOR CHECK-FLO-RATER® PISTON

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

→VIII. 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. 6.) 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

10 O'CLOCK

2 O'CLOCK

SENSING BULB

STRAP

SUCTION TUBE

8 O'CLOCK	4 O'CLOCK
7⁄8 IN. OD & SMALLER	LARGER THAN 7⁄8 IN. OD
	A81032

Fig. 5ÐPositioning of Sensing Bulb

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, substan- tial capacity and performance losses can occur. Following the recommendations in the Residential Split System Long-Line Application Guideline will reduce these losses. Refer to Table 1 for field tubing equivalent line length. Refer to Table 2 for accessory requirements.

→For buried-line applications greater than 36 in., refer to Table 2 and Residential Split System Buried-Line Application Guideline. Buried-line applications may not exceed 100 ft.

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 Indoor 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

A97517

Fig. 6ÐDefrost Thermostat Location

IX. 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., refer to Residen- tial Split System Buried-Line Application Guideline.

Ð3Ð

Connect tubing to fittings on outdoor unit vapor and liquid service valves. (See Table 1.) Use refrigerant grade tubing.

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. 7.) 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.