Receiver Location; Safety Relief Devices; Receiver Installation - Data Aire DAPA-2.5 Installation, Operation & Maintenance Manual

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.

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.

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.
See section 2.27 Refrigerant Piping Protection
over pressure protection.

Receiver Installation

Be sure the receiver capacity is large enough to store the winter charge during summer operations and
is generally designed so that receiver can hold at least the same volume as the condenser coil.
The receiver package(s) is typically mounted outdoors, near the condenser. If the receiver package(s)
are installed indoors, a check valve is required on the liquid line at the condenser outlet and a liquid
line relief valve.
When installing the Head Pressure Control Valve, be sure to place the sensing bulb on the liquid line
leaving the receiver and insulate it properly.
The temperature controller, which is supplied as part of the receiver package, will maintain the receiver
shell temperature at approximately 50°F (10C) which will keep the internal refrigerant at a pressure
high enough to allow cold ambient starting.
A check valve must be used in the liquid line between the flooded head pressure control valve and the
receiver to prevent refrigerant from migrating from the warm receiver back to the cold condenser during
the off cycle.
Pipe routing of the Head Pressure Control Valve must not trap any oil when operating in the summer
conditions.
for additional information regarding piping and receiver
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