Carrier 19XL specifications Pumpout and Refrigerant Transfer Procedures, Tstat

PUMPOUT AND REFRIGERANT TRANSFER

PROCEDURES

Preparation Ð The 19XL may come equipped with an optional storage tank or pumpout system, or a pump- out compressor. The refrigerant can be pumped for service work to either the cooler/compressor vessel or the condenser vessel by using the optional pumpout system. If a storage tank is supplied, the refrigerant can be isolated in the external storage tank. The following procedures describe how to transfer refrigerant from vessel to vessel and perform chiller evacuations.

Operating the Optional Pumpout Compressor

1.Be sure that the suction and the discharge service valves on the optional pumpout compressor are open (back- seated) during operation. Rotate the valve stem fully coun- terclockwise to open. Frontseating the valve closes the refrigerant line and opens the gage port to compressor pressure.

2.Make sure that the compressor holddown bolts have been loosened to allow free spring travel.

3.Open the refrigerant inlet valve on the pumpout compressor.

4.Oil should be visible in the pumpout compressor sight glass under all operating conditions and during shut- down. If oil is low, add oil as described under Optional Pumpout System Maintenance section, page 65. The pumpout unit control wiring schematic is detailed in Fig. 34.

TO READ REFRIGERANT PRESSURES during pumpout or leak testing:

1.The LID display on the chiller control center is suitable for determining refrigerant-side pressures and low (soft) vacuum. For evacuation or dehydration measurement, use a quality vacuum indicator or manometer to ensure the desired range and accuracy. This can be placed on the Schrader connections on each vessel by removing the pres- sure transducer.

2.To determine storage tank pressure, a 30 in.-0-400 psi (-101-0-2760 kPa) gage is attached to the vessel.

3.Refer to Fig. 27, 28, and 35 for valve locations and numbers.

Transfer, addition, or removal of refrigerant in spring- isolated chillers may place severe stress on external pip- ing if springs have not been blocked in both up and down directions.

Chillers with Pumpout Storage Tanks Ð If the chiller has isolation valves, leave them open for the follow- ing procedures. The letter ``C'' describes a closed valve. See Fig. 16, 17, 27, and 28.

TRANSFER REFRIGERANT FROM STORAGE TANK TO CHILLER

1.Equalize refrigerant pressure.

a.Use the Control Test Terminate Lockout to turn on water pumps and monitor pressures.

b.Close pumpout unit/storage tank valves 2, 4, 5, 8, and 10 and close chiller charging valve 7; open chiller iso- lation valves 11, 12, 13, and 14 (if present).

c.Open pumpout unit/storage tank valves 3 and 6, open chiller valves 1a and 1b.

LEGEND

CÐ Contactor

FU	Ð Fuse, 3 Amps
HP	Ð High-Pressure Cutout
OL	Ð Compressor Overload
T'STAT	Ð Internal Thermostat
	Compressor Terminal
	Contactor Terminal
	Overload Terminal
	Pumpout Unit Terminal

*Bimetal thermal protector imbedded in motor winding.

Fig. 34 Ð 19XL Pumpout Unit

Wiring Schematic

OIL RETURN	VENT VALVE 8
LINE
CONNECTION

												PUMPOUT
												STARTER
												PANEL
CONDENSER				REFRIGERANT
WATER
				INLET VALVE
CONNECTIONS
Fig. 35 Ð Optional Pumpout Unit
VALVE	1a	1b	2	3	4	5	6	7	8	10	11	12	13	14
CONDITION			C		C C			C C		C

d.Gradually crack open valve 5 to increase chiller pres- sure to 68 psig (469 kPa), [35 psig (141 kPa)]. Slowly feed refrigerant to prevent freeze up.

e.Open valve 5 fully after the pressure rises above the freeze point of the refrigerant. Open liquid line valves 7 and 10 until refrigerant pressure equalizes.

VALVE	1a	1b	2	3	4	5	6	7	8	10	11	12	13	14
CONDITION			C		C				C

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