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receivers is that they contain both liquid and gaseous refrigerant at the same time. By their
design, receivers prohibit liquid subcooling from occurring. Without liquid subcooling the
capacity of the system is reduced, and care must be taken in the design of the liquid line to avoid
flashing at the expansion valve.
Flooded systems are an excellent method of providing head pressure control in cold climates,
but they increase initial cost, add complexity to the refrigeration system, increase installation
time, and increase the refrigerant charge. The loss of subcooling should be recognized. If a
flooded system is required, consult the Data Aire prior to installation.
7.9.2. Applications
Liquid Refrigerant Receivers are installed in air conditioning and refrigeration systems. The
receiver is installed after the condenser in order to collect the condensed refrigerant to allow a
continuous liquid supply to the expansion device. Liquid receivers are also used to store the
refrigerant charge while the system is pumped down for service or maintenance.
7.9.3. Selection Guidelines
Receiver storage capacities are based on the liquid occupying no more than 90% of the internal
volume when the temperature of the refrigerant is 90°F (32°C) per ASHRAE Standard 15-78.
Includes within Data Aire’ Product Selector Guide, the low ambient receiver package has already
sized and selected for each Ultra model size.
It is essential that the maximum operating charge be determined, e.g., winter charge in air cooled
condenser having flooded head pressure control, this being much greater than the normal
summer charge.
7.9.4. Receiver Location
The low ambient receiver package can be ordered as a unit-mounted system or as a shipped
loose system. If the low ambient receiver package is unit-mounted system, the complete
package will be factory mounted and wired integral to the air-cooled condenser.
If the low ambient receiver package is shipped loose, it is the responsibility of the installing
contractor to mount the receiver package in a suitable location outdoors, near the air-cooled
condenser, and to connect the piping and electrical wiring, as requirement.
7.9.5. Safety Relief Devices
Data Aire
’s low ambient receiver(s) include a suitable fusible plug safety relief device installed
on the receiver housing. The fusible plug is a onetime discharge device and must be replaced
in the event of a receiver over temperature condition. The fusible plug allows refrigerant to
release at a controlled rate and relieves an over-temperature/pressure condition in the receiver.
2.18 Refrigerant Piping Protection
for additional information regarding piping and
receiver over-pressure protection.
7.10. Energy Saver Cooling (Optional)
In colder climates, the evaporator will often be equipped with an additional free cooling coil to
take advantage of the colder ambient temperatures. When incoming fluid falls below the set