Carrier 19EA - Manual

Carrier
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 and
INSTRUCTIONS:
MATERIALS:
wiring,
piping
Starter diagrams
Special controls and related
wiring (if any)
19EA Installation book
19EA Operating and Main­
tenance book
Starter Instructions
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
1. Unishell holding charge
and utility vessel refrig­
erant level unchanged.
4
2 Unishell holding charge
decreased slightly.
3 and 4 on unishell
3. Utility vessel refrigerant
level decreased slightly.
Leak test with halide or
electronic leak detector.
4. Unishell holding charge
completely gone Opened
valve or other open con­
nection suspected.
1
5 Unishell holding charge
completely gone Vessel
leak assumed
'2., 3, and 4 on unishell
6 Refrigerant charge in
utility vessel completely
gone. Opened valve or
, \ other open connection
suspected.
1 - Use nitrogen with
R-12 tracer in pressur­
izing for leak test pro­
cedures 2 and 3
7 Refrigerant charge in
utility vessel completely
gone. Vessel leak
assumed
2, 3/ and 4 on uti! ity
vessel. Use nitrogen with
R-12 tracer for pressuriz­
ing in 2 and 3
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
19EA 500, 550
19EA 590, 630 2000
2200
2400
Form 1PFA-1.S?;