PRGF-SVN001B-EN
9
Installation
Removing Old Purge Unit
Replacing an existing purge unit with the new EarthWise™
purge requires that the existing purge system be
disconnected and removed from the chiller. To be certain
that the retrofit procedure is performed properly, carefully
review the instructions in this section.
WARNING
Explosion Hazard and Deadly Gases!
Failure to follow all proper safe refrigerant handling
practices could result in death or serious injury. Never
solder, braze or weld on refrigerant lines or any unit
components that are above atmospheric pressure or
where refrigerant may be present. Always remove
refrigerant by following the guidelines established by
the EPA Federal Clean Air Act or other state or local
codes as appropriate. After refrigerant removal, use dry
nitrogen to bring system back to atmospheric pressure
before opening system for repairs. Mixtures of
refrigerants and air under pressure may become
combustible in the presence of an ignition source
leading to an explosion. Excessive heat from soldering,
brazing or welding with refrigerant vapors present can
form highly toxic gases and extremely corrosive acids.
WARNING
Hazardous Voltage!
Failure to disconnect power before servicing could
result in death or serious injury. Disconnect all electric
power, including remote disconnects before servicing.
Follow proper lockout/tagout procedures to ensure the
power can not be inadvertently energized. Verify that
no power is present with a voltmeter.
Preparation
Before actual removal of the old purge system can begin,
perform the following procedures to prepare the unit for
the removal procedure.
1. Shut the chiller down and disconnect all electrical
power.
2. Remove refrigerant charge from the chiller.
3. Evacuate the chiller to 4 mm Hg (0.53 kPa) to remove all
refrigerant vapor.
4. Pressurize chiller with dry nitrogen until the evaporator
pressure gauge indicates 0 psig.
5. Close the angle valve on the condenser to isolate the
purge tank refrigerant inlet line.
6. Close the angle valve on the evaporator (if present) to
isolate the purge tank liquid return line or carbon tank
regeneration.
Purge Removal Procedure
Disconnecting Electrical Connections
Disconnect all electrical connections at the connection
points provided in the existing purge unit control panel
and in the chiller control panel.
Purge Water Connections
Disconnect the existing water supply and return lines to
the purge tank (if applicable). These lines may be capped
off or dismantled since the EarthWise™ purge system
does not require water connections.
Purge Refrigerant Connections
1. Disconnect and remove the existing vapor line (if not 5/
8”) from the unit condenser to the purge compressor
inlet. This line will be replaced with a 5/8” line from the
condenser to the new purge tank inlet connection
during the purge installation procedure.
2. Remove the existing 1/2” shutoff valve (if present)
from the fitting on the condenser shell. This valve will
be replaced during the purge installation procedure.
3. Disconnect the 1/4” copper liquid return line from the
purge tank to the shutoff valve on the evaporator or
condenser (if present). The liquid return line must be 3/
8”.
Note:
The 1/4” line may be reused for the carbon
regeneration line if the length is sufficient.)
4. Remove the shutoff valve from the evaporator or
condenser if it is not 3/8” or larger.
Removing Old Purge Unit
Usually, the existing purge unit is mounted on an integral
base located on the upper surface of one of the unit
condensers. Unbolt the base from its mounting brackets
and remove the purge unit from its mounting location.
CAUTION
Heavy Objects!
Proper lifting equipment must be present to remove the
existing purge and mount the EarthWise™ purge. Use
of a step ladder may be necessary. Failure to follow
these safety procedures may result in minor injury or
equipment damage.
EarthWise™ Purge Installation
Replacing an existing older model purge unit with the
EarthWise purge requires a number of wiring and
hardware changes. To insure that the EarthWise purge
retrofit procedure is performed properly, carefully review
the instructions in this section.
Summary of Contents for EarthWise Purge
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