Bryant 575C, 575B IV A180 Cooling Mode Operation See Fig, 541A180 Heating Mode Operation See Fig

IV. 541A180 COOLING MODE OPERATION (See Fig. 22)

1.High pressure, high temperature refrigerant vapor from the compressor flows through the reversing valve and is directed to the outdoor coil vapor header.

2.At the outdoor coil vapor header, the high pressure, high temperature refrigerant vapor flows up to check valve “A” that blocks the flow. All the refrigerant is then directed to flow into the coil circuits.

3.Subcooled refrigerant liquid leaves the coil circuits entering the portion of the vapor header which is above check valve “A”. Check valve “C” is closed, therefore, the liquid refrigerant passes through check valve “B,” which is open, and enters the liquid line and goes to the indoor coil.

4.The liquid refrigerant is expanded and evaporated in the indoor coil resulting in low pressure vapor. This low pressure vapor returns to the outdoor unit through the system vapor line, reversing valve, and accumulator, reentering the compressor at the suc- tion connection.

V.541A180 HEATING MODE OPERATION (See Fig. 23)

1.High pressure, high temperature refrigerant vapor from the compressor flows through the reversing valve and is directed through the system vapor line to the indoor coil. Refrigerant is condensed and subcooled in the indoor coil and returns to the outdoor unit through the system liquid line.

2.Check valve “B” blocks the flow of liquid and the refrigerant is then directed to flow through check valve “C” (which is open), through the filter drier, and into the liquid header assembly.

3.The liquid refrigerant is expanded as it passes through the capillary tubes into outdoor coil circuits. The refrigerant evaporates as it passes through the coil circuits resulting in low pressure vapor.

4.The low pressure vapor leaves the coil circuits and enters the vapor header, check valve “A” is open, and returns to the compressor through the vapor line, reversing valve, and accumulator, reentering the compressor at the suction connection.

VI. CRANKCASE HEATER

The crankcase heater prevents refrigerant migration and compressor oil dilution during shutdown when compressor is not operating.

Close both compressor service valves when crankcase heater is deenergized for more than 6 hours.

VII. OUTDOOR UNIT FANS

Each fan is supported by a formed-wire mount bolted to the fan deck and covered with a wire guard. On the 541A180, the exposed end of the motor shaft is covered with a rubber boot. In case a fan motor must be repaired or replaced, be sure the rubber boot is put back on when the fan is reinstalled and be sure the fan guard is in place before starting the unit.

VIII. LUBRICATION

Fan motors have permanently sealed bearings. No further lubrication is required.

COMPRESSOR

REVERSING VALVE
VAPOR LINE		FROM
		INDOOR
ACCUMULATOR	BALL	UNIT
	VALVE

CK VALVE B

CK VALVE A

CK VALVE C

FILTER	FILTER
DRIER	DRIER

FIXED ORIFICE	LIQUID LINE		TO
			INDOOR
METERING DEVICE
		BALL	UNIT
		VALVE

Fig. 20 — 575C090,120 Cooling Mode (Size 090 Shown)

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