Carrier 19XR, XRV specifications Initial Start-Up, Refrigerant HFC-134a Charge

Models: 19XR XRV

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Table 10 — Refrigerant (HFC-134a) Charge

CHILLER EQUALIZATION WITH PUMPOUT UNIT — The following steps describe how to equalize refrigerant pres- sure on an isolated 19XR chiller using the pumpout unit.

1.Access the terminate lockout function on the CONTROL TEST screen.

2.IMPORTANT: Turn on the chilled water and con- denser water pumps to prevent freezing.

3.Open valve 4 on the pumpout unit and open valves 1a and 1b on the chiller cooler and condenser, Fig. 29 and 30. Slowly open valve 2 on the pumpout unit to equalize the pressure. This process takes approximately 15 minutes.

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 prevents the valve from opening or closing during service work or during chiller operation.

The full refrigerant charge on the 19XR will vary with chill- er components and design conditions, as indicated on the job data specifications. An approximate charge may be determined by adding the condenser charge to the cooler charge as listed in Table 10.

Always operate the condenser and chilled water pumps whenever charging, transferring, or removing refrigerant from the chiller.

Use the CONTROL TEST terminate lockout function to monitor conditions and start the pumps.

If the chiller has been shipped with a holding charge, the refrigerant is added through the pumpout charging connection (Fig. 29 and 30, valve 1b). First evacuate the nitrogen holding charge from the chiller vessels. Charge the refrigerant as a gas until the system pressure exceeds 35 psig (141 kPa) for HFC-134a. After the chiller is beyond this pressure the refrig- erant should be charged as a liquid until all the recommended refrigerant charge has been added. The charging valve (Fig. 29 and 30, valve 7) can be used to charge liquid to the cooler if the cooler isolation valve (11) is present and is closed. Do not charge liquid through the linear float to the condenser.

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

Table 10 lists the 19XR chiller refrigerant charges for each cooler and condenser code. Total refrigerant charge is the sum of the cooler and condenser charge.

Table 10 — Refrigerant (HFC-134a) Charge

COOLER

REFRIGERANT

CONDENSER

REFRIGERANT

CHARGE

CHARGE

CODE

 

 

CODE

 

 

lb

kg

lb

kg

 

 

10

290

132

10

200

91

11

310

141

11

200

91

12

330

150

12

200

91

15

320

145

15

250

113

16

340

154

16

250

113

17

370

168

17

250

113

20

345

157

20

225

102

21

385

175

21

225

102

22

435

197

22

225

102

30

350

159

30

260

118

31

420

190

31

260

118

32

490

222

32

260

118

35

400

181

35

310

141

36

480

218

36

310

141

37

550

250

37

310

141

40

560

254

40

280

127

41

630

286

41

280

127

42

690

313

42

280

127

45

640

290

45

330

150

46

720

327

46

330

150

47

790

358

47

330

150

50

750

340

50

400

181

51

840

381

51

400

181

52

900

408

52

400

181

55

870

395

55

490

222

56

940

426

56

490

222

57

980

445

57

490

222

60

940

426

60

420

190

61

980

445

61

420

190

62

1020

463

62

420

190

65

1020

463

65

510

231

66

1060

481

66

510

231

67

1090

494

67

510

231

70

1220

553

70

780

354

71

1340

608

71

780

354

72

1440

653

72

780

354

75

1365

619

75

925

420

76

1505

683

76

925

420

77

1625

737

77

925

420

80

1500

680

80

720

327

81

1620

735

81

720

327

82

1730

785

82

720

327

85

1690

766

85

860

390

86

1820

825

86

860

390

87

1940

880

87

860

390

INITIAL START-UP

Preparation — Before starting the chiller, verify:

1.Power is on to the main starter, oil pump relay, tower fan starter, oil heater relay, and the chiller control panel.

2.Cooling tower water is at proper level and at-or-below design entering temperature.

3.Chiller is charged with refrigerant and all refrigerant and oil valves are in their proper operating positions.

4.Oil is at the proper level in the reservoir sight glasses.

5.Oil reservoir temperature is above 140 F (60 C) or above refrigerant temperature plus 50° F (28° C).

6.Valves in the evaporator and condenser water circuits are open.

NOTE: If the pumps are not automatic, ensure water is circulating properly.

Do not permit water or brine that is warmer than 110 F (43 C) to flow through the cooler or condenser. Refrigerant overpressure may discharge through the relief valves and result in the loss of refrigerant charge.

7.Access the CONTROL TEST screen. Scroll down on the TERMINATE LOCKOUT option. Press the SELECT (to enable the chiller to start) and answer YES to reset unit to operating mode. The chiller is locked out at the factory in order to prevent accidental start-up.

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Page 64
Image 64
Carrier 19XR, XRV specifications Initial Start-Up, Refrigerant HFC-134a Charge