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ermetic Centrifugal Liquid Chillers
INTRODUCTION
persons concerned with the start-up and ope^ion of the 19EA machine should understand thteie instructions and all necessary job data before initial start-up. Instructions are in proper sequence for optimum machine performance.
Data and Equipment Required
PRINTS: |
Machine assembly wiring, and |
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piping |
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Starter diagrams |
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Special controls and related |
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wiring (if any) |
INSTRUCTIONS: 19EA Installation book 19EA Operating and Main tenance book
Starter Instructions
MATERIALS: Mechanics’ tools, electronic or halide leak detector, clamp-on ammeter, volt-ohmmeter
INITIAL PREPARATIONS
Machine Tightness — The 19EA is shipped with the refrigerant charge in the utility vessel and a holding charge (10 psig) in the unishell. Several levels of leak testing may be required depending on condition of machine on arrival and at start-up. Determine machine condition and follow pro cedure indicated in Table 1.
For transferring refrigerant and evacuating vessels, follow the pumpout instructions on pages 3 and 4.
Table 1 — Selection of Leak Test Procedures
MACHINE CONDITION |
PROCEDURE |
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1. Unishell holding charge |
4 |
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and utility vessel refrig |
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erant level unchanged. |
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2 Unishell holding charge |
3 and 4 on unishell |
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decreased slightly. |
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3. Utility vessel refrigerant |
Leak test with halide or |
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level decreased slightly. |
electronic leak detector. |
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4. Unishell holding charge |
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completely gone Opened |
1 |
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valve or other open con |
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nection suspected. |
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5 Unishell holding charge |
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completely gone Vessel |
'2., 3, and 4 on unishell |
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leak assumed |
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6 Refrigerant charge in |
1 - Use nitrogen with |
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utility vessel completely |
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R-12 tracer in pressur |
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gone. Opened valve or |
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izing for leak test pro |
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, \ other open connection |
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cedures 2 and 3 |
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suspected. |
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7 Refrigerant charge in |
2, 3/ and 4 on uti! ity |
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utility vessel completely |
vessel. Use nitrogen with |
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gone. Vessel leak |
R-12 tracer for pressuriz |
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assumed |
ing in 2 and 3 |
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Nev«f charge Squid refr^erant into the unisheii if vessd isressarc is beiow 3S ps^.., or vtaife water pumps itoi op«ratirig. Cooler tube freeze-trp and. dam^e may rearlt,
PROCEDURE 1 — Standing Vacuum Test
1. Attach a mercury manometer (absolute pressure-type) to the refrigerant charging valve,
(6) Fig. 1. A dial-type gage cannot indicate the small amount of leakage acceptable during a short period of time.
2.Pull a vacuum on the vessel (see evacuating procedures on page 3) equal to 25 in. Hg, ref 30-in. bar. (2.5 psia), using the pumpout system pump.
3.Valve off pump to hold vacuum, and record manometer reading.
4.If the leakage rate is less than 0.05 in. Hg/24 hours, perform procedure 3, aU steps under Machine Dehydration and procedure 4.
5.If the leakage rate exceeds 0.05 in. Hg/24 hours, perform procedures 2, 3, all steps under Machine Dehydration, and procedure 4 in the order indicated.
6.Remove mercury manometer from refrigerant charging valve.
PROCEDURE 2 — Follow steps 1 thru 4 of Return Refrigerant to Normal Operating Conditions, page 3. Raise vessel pressure slowly to 5 psig by cracking open valve 4. Perform leak test with hahde or electronic detector and repair any leaks.
PROCEDURE 3 — Following steps 1 thru 5 of Return Refrigerant to Normal Operating Condi tions, page 3, raise vessel pressure to 35 psig. Perform leak test with halide or electronic detector and repair any leaks.
PROCEDURE 4 — Equalize pressure between utility vessel and unishell following steps 1 thru 5 of Return Refrigerant to Normal Operating Conditions, page 3. Vessel pressure will be approxi mately 70 psig. Perform leak test with halide or electronic detector and repair any leaks.
If refrigerant charge was lost and nitrogen has been used for pressurizing in procedures 2 and 3, evacuate vessel and then charge 400 lb of R-12 for procedure 4. If vessels are then leak tight, continue charging refrigerant to the level indicated in Charging Quantity Table below.
Table 2 — Charging Quantity
MACHINE SIZE |
WEIGHT (lb R-12) |
19EA 400, 430, 465 |
2000 |
19EA 500, 550 |
2200 |
19EA 590, 630 |
2400 |
Form 1PFA-1.S?;
COMPRESSOR MOTOR |
COMPRESSOR |
TERMINAL BOX |
MOTOR DRIVE |
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e, add
CONDENSER |
REAR VIEW |
SECTION |
COMPRESSOR
/ MOTOR DRIVE
CONDENSER
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CONTROL BOX |
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FRONT VIEW |
PUMPOUT UNIT |
COMPRESSOR |
COOLER |
UNISHELL |
LEGEND
1 Pumpout Service Valve 1 |
20. Sight Glass — Rotation |
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2 Pumpout Service Valve 2 |
21. Sight Glass — Seal Oil |
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3 |
Pumpout Service Valve 3 |
22 |
Sight Glass — Liquid Level |
4. Pumpout Service Valve 4 |
23 |
Sight Glass — Liquid Level |
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5 |
Pumpout Service Valve 5 |
24. Sight Glass — Liquid Level |
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6 |
Pumpout Service Valve 6 and Refrigerant Charging Valve |
25 |
Sight Glass — Liquid Level |
7. Pumpout Service Valve 7 |
26 |
Refrigerant Drain Valve |
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8 Pumpout Service Valve 8 |
27. |
Isolation Valve |
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9. Service Valve 9 (hidden between unishell and utility vessel) |
28 |
Isolation Valve (hidden) |
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10 |
Differential Pressure Gage (oil) |
29. |
Isolation Valve |
11 |
Condenser Pressure Gage |
30. Isolation Valve — ball valve between unishell |
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12 |
Cooler Pressure Gage |
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and utility vessel (hidden) |
13. Dehydrator Water Valve |
31 Chilled Water Control Element |
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14 |
Oil Level Sight Glass |
32 |
Pumpout Vent Valve with Flare Cap |
15 |
Oil Temperature Gage |
33. |
Bearing Return Oil Thermometer (hidden) |
16 |
Oil Heater (with indicator light) |
34 |
Dehydrator Pressure Gage |
17. Oil Heater Thermostat |
35 Dehydrator Discharge Hand Valve |
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18 Oil Pressure Regulating Valve |
36. |
Oil Cooler Plug Cock |
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19 Oil Reservoir Charging Valve |
37 Chilled Water Lo-Temp Cutout |
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Fig. 1 — Machine Components
ISOLATION VALVE OPERATION
Opening — Compressor must be off and vessel pressures equalized (see Return Refrigerant to Normal Operating Condition, steps 1 thru 6).
^.Loosen packing nut 1/2 to 1 turn so valve stem will rotate and slide smoothly in packing. Do not let refrigerant trapped in valve body escape.
2.Hold stem in against line pressure and rotate stem counterclockwise as far as possible.
3.Slide stem out of body.
4i Rotate stem clockwise in the out position, until snug.
5. Tighten packing nut. Closing
1. Loosen packing nut 1/2 to 1 turn so valve stem will rotate and slide smoothly in packing. Do not let refrigerant trapped in valve body escape.
2.Rotate valve stem counterclockwise as far as possible.
3.Slide stem into valve until it bottoms.
4.Rotate stem clockwise, holding assembly in, until it is tight (25 ft-lb).
5.Tighten packing nut.
TRANSFER REFRIGERANT FROM UTILITY VESSEL TO UNI SHELL* from normal operating condition.
1.Add manometer near charging valve 6.
2.Close isolation valves (27), (28), and (30).
3.Open valves 1, 3, 4, 6, 7 and 8.
4.Close valves 2, 5 and 9.
5.Ensure that pumpout condenser water is off.
6.Turn on pumpout compressor until liquid is out of utility vessel.
7.Turn off pumpout compressor.
8.Close isolation valve (29).
9.Close valves 3 and 4.
10.Open valves 1 , 2 , 5 and 6.
1 1 . Turn on pumpout condenser water.
12. Run pumpout compressor until utility vessel pressure reaches 25 in. Hg, ref 30-in. bar. (2.5 psia).
13.Turn off pumpout compressor.
14.Close valves 1, 2, 5 and 6.
15.Turn off pumpout condenser water.
TRANSFER REFRIGERANT FROM UNISHELL TO UTILITY VESSEL* from normal operating condition.
1.Open drain valve (26).
2.Wait one hour; close isolation valves (27), (28) and (30).
3.Open valves 1 , 2 , 5, 6, 7 and 8.
4.Close valves 3 and 4.
5.Ensure that pumpout condenser water is off.
6.Turn on pumpout compressor for 20 minutes.
7.Turn off pumpout compressor.
8.Close isolation valve (29). Close valves 2 and 5.
10.Open valves 1, 3, 4 and 6.
11. Turn on cooler and condenser pumps and pumpout condenser water.
Fig. 2 — Pumpout System Schematic (See Fig. 1 Legend for Item Ref)
12.Run pumpout compressor until unishell pres sure reaches 25 in. Hg, ref 30-in. bar. (2.5 psia). Use dehydrator gage (34) for pressure reading.
13.Turn off pumpout compressor.
14.Close valves 1, 3, 4 and 6.
15.Turn off pumpout condenser water.
UTILITY VESSEL EVACUATING PROCEDURE*
1.Close valves 1 , 2 , 3, 4 and 9.
2.Open valves 5 , 6 , 1 and 8.
3.Open vent valve (32) and remove flare cap.
4.Turn off pumpout condenser water.
5.Operate pumpout compressor until manometer reads 25 in. Hg, ref 30-in. bar. (2.5 psia).
6.Close valves 5, 6, 7 and 8.
7.Shut off pumpout compressor.
8.Close vent valve (32) and replace flare cap.
UNISHELL EVACUATING PROCEDURE*
1.Close valves 2, 4, 6 and 9.
2.Open valves 1, 3 and 5.
3.Open vent valve (32) and remove flare cap.
4.Turn off pumpout condenser water.
5.Operate pumpout compressor until manometer reads 25 in. Hg, ref 30-in. bar. (2.5 psia).
6.Close valves 1, 3 and 5.
7.Shut off pumpout compressor.
8.Close vent valve (32) and replace flare cap.
RETURN REFRIGERANT TO NORMAL OPER ATING CONDITION *
1.Ensure that opened vessel has been evacuated.
2.Close valves 3, 4 and 5.
3.Open valves 1 , 2 , 6, 7 and 8.
4.Run water pumps.
5a. If unishell has been evacuated — Crack open valve 4, gradually increasing pressure in uni shell to 35 psig. Feed refrigerant slowly to prevent tube freeze-up.
*See Fig 1 and 2 for all numbered references.
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