Carrier Refrigerant Charges, 19XL Total Refrigerant Charge, Cooler, Size, HCFC-22

19XL CHILLER EQUALIZATION WITH PUMPOUT UNIT Ð The following procedure describes how to equal- ize refrigerant pressure on an isolated 19XL chiller using the pumpout unit.

1.Access the TERMINATE LOCKOUT mode in the Con- trol Test.

2.Turn on the chilled water and condenser water pumps to prevent possible freezing.

3.Open valve 4 on the pumpout unit and open valves 1a and 1b on the chiller cooler and condenser, Fig. 27 and

28.Slowly open valve 2 on the pumpout unit to equalize the pressure. This process will take approximately

15minutes.

4.Once the pressures have equalized, the discharge isola- tion valve, cooler isolation valve, optional hot gas bypass isolation valve, and the refrigerant isolation valve can be opened. Close valves 1a and 1b, and all pumpout unit valves.

Whenever turning the discharge isolation valve, be sure to reattach the valve locking device. This will prevent the valve from opening or closing during serv- ice work or during chiller operation.

The full refrigerant charge on the 19XL will vary with chiller components and design conditions, indicated on the job data speci®cations. An approximate charge may be found by adding the condenser charge to the cooler charge listed in Table 8.

Always operate the condenser and chilled water pumps during charging operations to prevent freeze-ups. Use the Control Test Terminate Lockout to monitor conditions and start the pumps.

If the chiller has been shipped with a holding charge , the refrigerant will be added through the refrigerant charging valve (Fig. 27 and 28, valve 7) or to the pumpout charging con- nection. First evacuate the nitrogen holding charge from the

vessels. Charge the refrigerant as a gas until the system pres- sure exceeds 68 psig (469 kPa); [35 psig (141 kPa)]. After the chiller is beyond this pressure the refrigerant should be charged as a liquid until all of the recommended refrigerant charge has been added.

TRIMMING REFRIGERANT CHARGE Ð The 19XL is shipped with the correct charge for the design duty of the chiller. Trimming the charge can be best accomplished when design load is available. To trim, check the temperature difference between leaving chilled water temperature and cooler refrigerant temperature at full load design conditions. If necessary, add or remove refrigerant to bring the tempera- ture difference to design conditions or minimum differential.

	Table 8 Ð Refrigerant Charges*
		19XL TOTAL REFRIGERANT CHARGE
COOLER		Design I			Design II
					Chiller
SIZE		Chiller
				HCFC-22		HFC-134a
		lb	kg	lb	kg	lb	kg
40		1420	640	1100	499	900	409
41		1490	680	1150	522	950	431
42		1550	700	1250	568	1000	454
43		1600	730	1350	613	1050	477
50		1850	840	1500	681	1100	499
51		1900	860	1600	726	1200	545
52		1980	900	1750	795	1300	590
53		2050	930	1850	840	1350	613
55		Ð	Ð	1900	863	1550	704
56		Ð	Ð	2200	999	1650	749
57		Ð	Ð	2500	1135	1750	795
58		Ð	Ð	2700	1226	1900	863

*Design I chillers use HCFC-22. Design II chillers use either HCFC-22 or HFC-134a.

NOTES:

1.The size of the cooler determines refrigerant charge for the entire chiller.

2.Design I chillers have ¯oat chambers.

3.Design II chillers have linear ¯oats.

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