87
equal to or less than 35 psig (241 kPa) to reduce
the potential of tube damage.
k. Run the pumpout compressor until the condenser
refrigerant pressure reaches 35 psig (241 kPa) then
turn off the pumpout compressor. Warm condenser
water will boil off any entrapped liquid refrigerant,
and chiller pressure will rise. Repeat this process
until the chiller pressure no longer rises.
l. Run pumpout unit in auto until the vacuum switch
is satisfied; this occurs at approximately 15 in. Hg
vacuum (48 kPa absolute or 7 psia). Close
valve 1B.
m. Monitor that condenser pressure does not rise (if it
does, then repeat previous step).
n. With service valve 1B closed, shut down pumpout
compressor (if still running).
o. Close remaining valves.
p. Turn off pumpout condenser water.
q. Turn off chiller water pumps, and lock out chiller
compressor.
Return Chiller to Normal Operating Conditions
1. Vapor Pressure Equalization:
a. Ensure that the chiller vessel that was exposed to
ambient has been evacuated. Final vacuum prior to
charging with refrigerant should in all cases be
29.9 in. Hg (500 microns, 0.07 kPa [abs]) or less.
b. Turn on chiller water pumps.
c. Open valves 1A, 1B, and 2.
d. Slowly open valve 4, gradually increasing pressure
in the evacuated vessel to 35 psig (241 kPa).
e. Leak test to ensure chiller vessel integrity.
f. Open valve 4 fully for cooler and condenser pres-
sure equalization (vapor equalization).
g. Close valves 1A, 1B, 2, and 4.
2. Liquid equalization:
a. If refrigerant is stored in cooler, install a charging
hose between valves 7 and 8, and open both the
valves and any other isolation valves (except valve
11) for liquid to drain into the condenser while
bypassing the linear float valve. If refrigerant is
stored in the condenser, keep valve 11 and any
other isolation valves open for liquid drain.
b. If valves 7 and 8 were used to bypass the linear
float valve, once the liquid transfer is complete,
close these valves, and slowly open valve 11.
c. Turn off chiller water pumps.
DISTILLING THE REFRIGERANT
1. Transfer the refrigerant from the chiller to the pumpout
storage tank as described in the Transfer the Refrigerant
from Chiller to Pumpout Storage Tank section.
2. Equalize the refrigerant pressure.
a. Turn on chiller water pumps and monitor chiller
pressures.
b. Close pumpout and storage tank valves 2, 4, 5, and
10, and close chiller charging valve 7; open chiller
isolation valve 11 and any other chiller isolation
valves, if present.
c. Open pumpout and storage tank valves 3 and 6;
open chiller valves 1a and 1b.
d. Gradually crack open valve 5 to increase chiller
pressure to 35 psig (241 kPa). Slowly feed refriger-
ant to prevent freeze-up.
e. Open valve 5 fully after the chiller pressure rises
above the freezing point of the refrigerant. Let the
storage tank and chiller pressure equalize.
3. Transfer remaining refrigerant.
a. Close valve 3.
b. Open valve 2.
c. Turn on pumpout condenser water.
d. Run the pumpout compressor until the storage tank
pressure reaches 5 psig (34 kPa), 18 in. Hg vacuum
(41 kPa absolute) in Manual or Automatic mode.
e. Turn off the pumpout compressor.
f. Close valves 1a, 1b, 2, 5, and 6.
g. Turn off pumpout condenser water.
4. Drain the contaminants from the bottom of the storage
tank into a container. Dispose of contaminants safely.
GENERAL MAINTENANCE
Refrigerant Properties —
The standard refrigerant for
the 19XRV chiller is HFC-134a. At normal atmospheric
pressure, HFC-134a refrigerant will boil at –14 F (–25 C) and
must, therefore, be kept in pressurized containers or storage
tanks. The refrigerant is practically odorless when mixed with
air and is noncombustible at atmospheric pressure. Read the
Material Safety Data Sheet and the latest ASHRAE Safety
Guide for Mechanical Refrigeration to learn more about safe
handling of this refrigerant.
VALVE 1A1B23457811
CONDITION C C C C C C
VALVE 1A1B23457811
CONDITION CCCCCCCCC
VALVE 1A1B23457811
CONDITION C C C C C C
VALVE 1A1B23457811
CONDITION C C C C C
VALVE 1A1B23457811
CONDITION CCCCCCCCC
VALVE 1A1B23457811
CONDITION
(CHARGE IN
COOLER)
CCCCCC C
CONDITION
(CHARGE IN
CONDENSER)
CCCCCCCC
VALVE 1A1B2345671011
CONDITION C C C C C
VALVE 1A1B2345671011
CONDITION C C C C
VALVE 1A1B2345671011
CONDITION CCCCCCCCC
DANGER
Refrigerant HFC-134a will dissolve oil and some nonme-
tallic materials, dry the skin, and, in heavy concentrations,
may displace enough oxygen to cause asphyxiation. When
handling this refrigerant, protect the hands and eyes and
avoid breathing fumes.
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