12
NOTE: During this operation, maintain water circulation
through the chiller cooler and condenser vessels to prevent
tube freeze-up.
DISTILLING THE REFRIGERANT — Refrigerant vapor is
transferred from the chiller cooler vessel or pumpout storage
tank through the pumpout condenser, condensed to a liquid,
and pumped to the chiller condenser vessel. During this opera-
tion, water circulation must be maintained in the pump-out
condenser. Refrigerant impurities left in the chiller cooler ves-
sel or storage tank are then drained off. This operation can take
from 4 to 14 hours, depending on the type and amount of re-
frigerant being distilled.
The Pumpout and Refrigerant Transfer Procedures section
gives step-by-step instructions on performing these operations.
Pumpout and Refrigerant Transfer
Procedures
PREPARATION — The 19XR chiller may come equipped
with an optional pumpout storage tank, pumpout system, or
pumpout compressor. The refrigerant can be pumped for ser-
vice work to either the chiller compressor vessel or chiller con-
denser vessel by using the optional pumpout system. If a
pumpout storage tank is supplied, the refrigerant can be iso-
lated in the storage tank. The following procedures describe
how to transfer refrigerant from vessel to vessel and perform
chiller evacuation.
OPERATING THE OPTIONAL PUMPOUT UNIT (Fig. 9)
— Oil should be visible in the pumpout unit compressor sight
glass under all operating conditions and during shutdown. If oil
is low, add oil as described under Maintenance section, page
17. The pumpout unit control wiring schematic is detailed in
Fig. 8.
To Read Refrigerant Pressures (during pumpout or leak test-
ing):
1. The ICVC display on the chiller control panel is suitable
for determining refrigerant-side pressures and low (soft)
vacuum. To assure the desired range and accuracy when
measuring evacuation and dehydration, use a quality
vacuum indicator or manometer. This can be placed on
the Schrader connections on each vessel by removing the
pressure transducer.
2. To determine pumpout storage tank pressure, a 30 in. Hg
vacuum -0-400 psi (-101-0-2769 kPa) gage is attached to
the storage tank.
3. Refer to Fig. 10 and 11 for valve locations and numbers.
Positive Pressure Chillers With Storage Tanks — In the
Valve/Condition tables that accompany these instructions, the
letter “C” indicates a closed valve. Figures 9 and 10 show the
locations of the valves.
CAUTION
The power to the pumpout compressor oil heater must be
on whenever any valve connecting the pumpout compres-
sor to the chiller or storage tank is open. Leaving the heater
off will result in oil dilution by refrigerant and can lead to
compressor failure.
If the compressor is found with the heater off and a
valve open the heater must be on for at least 4 hours to
drive the refrigerant from the oil. When heating the oil the
compressor suction must be open to a vessel to give the re-
frigerant a means to leave the compressor.
CAUTION
Always run the chiller cooler and condenser water pumps
and always charge or transfer refrigerant as a gas when the
chiller pressure is less than 35 psig (241 kPa). Below these
pressures, liquid refrigerant flashes into gas, resulting in
extremely low temperatures in the cooler/condenser tubes
and possibly causing tube freeze-up.
DANGER
During transfer of refrigerant into and out of the optional
storage tank, carefully monitor the storage tank level gage.
Do not fill the tank more than 90% of capacity to allow for
refrigerant expansion. Overfilling may result in damage to
the tank or the release of refrigerant which will result in
personal injury or death.
CAUTION
Do not mix refrigerants from chillers that use different
compressor oils. Compressor damage can result. The
pumpout oil separator comes pre-charged with 13 oz of
ISO viscosity 220 POE (Polyol Ester) oil. The pumpout
compressor is approved for use with ISO viscosity 220
POE oil or ISO viscosity 68 POE oil. The pumpout com-
pressor is also factory precharged with oil.
CAUTION
Transfer, addition, or removal of refrigerant in spring-
isolated chillers may place severe stress on external piping
if springs have not been blocked in both up and down
directions.
CAUTION
Always run chiller cooler and condenser water pumps and
always charge or transfer refrigerant as a gas when chiller
vessel pressure is less than 35 psig (241 kPa). Below these
pressures, liquid refrigerant flashes into gas, resulting in
extremely low temperatures in the cooler/condenser tubes
and possibly causing tube freeze-up.
CAUTION
The power to the pumpout compressor oil heater must be
on whenever any valve connecting the pumpout compres-
sor to the chiller or storage tank is open. Leaving the heater
off will result in oil dilution by refrigerant and can lead to
compressor failure.
If the compressor is found with the heater off and a valve
open the heater must be on for at least 4 hours to drive the
refrigerant from the oil. When heating the oil the compres-
sor suction must be open to a vessel to give the refrigerant
a means to leave the compressor.
Summary of Contents for 19XR Series
Page 19: ......
