c l i m a t e m a s t e r.c o m
55
Tranquility
®
Large Water-to-Water (TMW) Series
R e v. : O c t o b e r 5 , 2 0 2 1
T H E S M A R T S O L U T I O N F O R E N E R G Y E F F I C I E N C Y
Refrigeration System Recharging
Refrigeration System Recharging -
Conforming to local
and national codes is the responsibility of the service
technician or installing contractor. The service technician
should be familiar with the following codes:
• ASHRAE Standard Safety Code for Mechanical
Refrigeration, ANSI/ASHRAE 15-1978
• American National Standard Code for Pressure Piping,
ANSI B31.5-1974
Factory Tested -
ClimateMaster units have been pressure-
tested, evacuated and fully charged and run tested at design
water flow rates prior to shipment. In the unlikely event
that a refrigerant leak is detected at start-up, the following
guidelines should be consulted before reprocessing the
refrigeration systems.
Refrigerant System Recharging -
Debris and moisture can
enter copper tubing in a matter of minutes. All tubing, coil
connections, or any refrigerant containing portions should
be temporarily capped or sealed to keep contaminants to a
minimum. Filter driers should be opened just prior to brazing
into the system to prevent moisture infiltration whenever
possible.
After all of the repairs have been made to the refrigeration
system, a pressure test using refrigerant and nitrogen should
be performed. Pressurize the system with dry nitrogen to 20
psi and check for any obvious leaks. If no leaks are present
introduce a “trace” amount of refrigerant to the system
(raise system pressure to 30-40 psi). With a dry nitrogen
tank equipped with a regulator set to 150 psi, continue to
pressurize the system to 150 psi. Using a leak detector,
carefully check the system for any remaining leaks. If the
system is free of leaks you may release the pressure.
Evacuating the System -
The compressors should never
be run while the system is in a vacuum. This could cause
immediate failure to the compressors. After the system has
been leak tested and sealed, any moisture that entered
the system should be dehydrated and removed. While
the pressure is reduced under a vacuum, the boiling point
of moisture trapped inside the lines is reduced also. A
pressure of .0095 PSIA, or 500 microns absolute pressure
or better must be reached and sustained for several hours
in order for the system to be considered free from moisture.
It is necessary to use a micron meter equipped with an
absolute pressure gauge (or transducer) to take this reading.
ClimateMaster recommends the double evacuation process
to ensure the proper removal of moisture and contaminants
from the refrigeration system. After the initial vacuum is
reached and held on the system, allow dry nitrogen back into
the system until the pressure reaches zero PSIG or slightly
higher. Then, repeat the entire evacuation process described
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WARNING!
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WARNING!
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WARNING!
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WARNING!
To avoid the release of refrigerant into the
atmosphere, the refrigerant circuit of this unit must be
serviced only by technicians who meet local, state and
federal proficiency requirements.
WARNING!
All refrigerant discharged from this unit must be
recovered WITHOUT EXCEPTION. Technicians must follow
industry accepted guidelines and all local, state and federal
statutes for the recovery and disposal of refrigerants.
WARNING!
If a compressor is removed from this unit,
system refrigerant circuit oil will remain in the compressor. To
avoid leakage of compressor oil, the refrigerant lines of the
compressor must be sealed after it is removed.
above. The evacuation process is considered complete
ONLY after a successful “blank-off” test is performed. A
“blank-off” test is defined as: a) pulling a vacuum level less
than 500 microns on the system and holding it for several
hours; b) record the vacuum level in the system in microns,
then close off the vacuum pump from the system for 15
minutes, and continue to monitor the micron level inside
the refrigeration system; c) if the vacuum level inside the
system does NOT rise more than 400 microns above the
recorded vacuum level at the start of the 15 minute period,
then the evacuation process is complete. If the vacuum level
rises more than 400 microns in 15 minutes, then continue
to evacuate the system for 1-2 hours, and then repeat a
“blank-off” test.
Recharging the System -
After all repairs have been
completed, the system has been leak tested, and proper
vacuum pressures have been reached and maintained,
refrigerant may be recharged into the system. With a
known weight of refrigerant in the cylinder, use the gage
manifold set to connect the cylinder’s liquid charging port
to the charging access port near the refrigerant liquid line
valve. Open the compressor suction and discharge line
valves. Gradually meter the appropriate weight of liquid
refrigerant into the condenser side of the system first,
until no additional refrigerant can be dispensed. Accurate
refrigerant charge per circuit may be found in the Physical
Data information on page 6. Then continue the charging
process by filling the evaporator side of the system with
refrigerant. Close the refrigerant cylinder charging port,
close all gage manifold ports and start the compressor.
Be careful when continuing to charge the balance of the
refrigerant, constantly maintaining a positive compressor
suction pressure (>25 PSIG) at all times.
