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CAUTION
When equalizing refrigerant pressure on the 19XR chiller after
service work or during the initial chiller start-up, do not use the
discharge isolation valve to equalize. A charging hose (con-
nected between the charging valves on top of the cooler and
condenser) should be used as the equalization valve. Failure to
follow this procedure may damage equipment.
CHILLER EQUALIZATION WITHOUT A PUMPOUT UNIT
To equalize the pressure differential on a refrigerant isolated 19XR
chiller, use the terminate lockout function PUMPDOWN/LOCK-
OUT (located in the Maintenance Menu). This helps to turn on
pumps and advises the operator on proper procedures.
The following steps describe how to equalize refrigerant pressure
in an isolated 19XR chiller without a pumpout unit.
1.
Access terminate lockout function on the Maintenance
Menu. (Alternatively, the Quick Test provides a means for
cooler and condenser pump control.)
IMPORTANT: Turn on the chilled water and condenser
water pumps to prevent freezing.
2.
Slowly open the refrigerant charging valves. The chiller
cooler and condenser pressures will gradually equalize.
This process takes approximately 15 minutes.
3.
Once the pressures have equalized, the cooler isolation
valve, the condenser isolation valve, and the hot gas isola-
tion valve may now be opened. Refer to Fig. 33 and 34 for
the location of the valves.
WARNING
Whenever turning the discharge isolation valve, be sure to re-
attach the valve locking device. This prevents the valve from
opening or closing during service work or during chiller opera-
tion. Failure to follow this procedure may damage equipment
and result in bodily injury.
CHILLER EQUALIZATION WITH FREE-STANDING
PUMPOUT UNIT
The following steps describe how to equalize refrigerant pressure
on an isolated 19XR chiller using the pumpout unit.
1.
Access the terminate lockout function on the PUMPDOWN/
LOCKOUT screen (located in the Maintenance Menu).
IMPORTANT: Turn on the chilled water and condenser
water pumps to prevent freezing.
2.
Open valve 4 on the pumpout unit and open valves 1a and
1b on the chiller cooler and condenser, Fig. 33 and 34.
Slowly open valve 2 on the pumpout unit to equalize the
pressure. This process takes approximately 15 minutes.
3.
Once the pressures have equalized, the discharge isolation
valve, cooler isolation valve, optional hot gas bypass isola-
tion valve, and 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 re-
attach the valve locking device. This prevents the valve from
opening or closing during service work or during chiller opera-
tion. Failure to follow this procedure may damage equipment
and result in bodily injury.
The full refrigerant charge on the 19XR chiller will vary with
chiller 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 the
Heat Exchanger Data tables in the Physical Data section that be-
gins on page 56.
Always operate the condenser and chilled water pumps when-
ever charging, transferring, or removing refrigerant from the
chiller. Always confirm that water flow is established. Failure
to follow this procedure may result in equipment damage.
Use the PUMPDOWN/LOCKOUT terminate lockout function to
monitor conditions and start the pumps.
If the chiller has been shipped with a holding charge, the refriger-
ant is added through the pumpout charging connection (Fig. 33
and 34, 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 (241 kPa) for HFC-134a or 39 psig
(268 kPa) for R-513A. After the chiller is beyond this pressure the
refrigerant should be charged as a liquid until all the recommend-
ed refrigerant charge has been added. The charging valve (Fig. 33
and 34, 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 backwards through any of the floats to the condenser.
TRIMMING REFRIGERANT CHARGE
The 19XR chiller is shipped with the correct charge for the design
duty of the chiller. Trimming the charge can best be accomplished
when the design load is available. To trim the charge, check the
temperature difference between the leaving chilled water tempera-
ture and cooler refrigerant temperature at full load design condi-
tions. If necessary, add or remove refrigerant to bring the tempera-
ture difference to design conditions or minimum differential.
See the 19XR Installation Instructions manual for required chiller
refrigerant charge or consult chiller nameplates.
If low load oil loss is experienced, operate the chiller at low load
with the guide vanes nearly closed and observe the flow through
the sight glass in the oil skimmer line. Under low load operation
one should be able to see a flow of bubbly oil and refrigerant in the
sight glass. If there is no visible flow, add refrigerant. If the sight
glass shows a flow of nearly clear fluid remove refrigerant.
35
WARNING
CAUTION
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