An evaporative condenser, air-cooled condenser, or tube-in-tube condenser that
does not provide subcooling needs a receiver to collect the condensed refrigerant
used by the system. The receiver, located between the condenser and the
expansion valve, stores the entire refrigerant charge if the system is pumped
down. It is usually nothing more than a steel tank with proper shut-off valves
and a safety relief device.
Large receivers should have a level gauge so that you can check the
refrigerant level easily. The liquid supply line leaving the receiver should exit at the bottom of the receiver. If it must exit at the top of the receiver, it should extend all the way to the bottom.