21
Figure 6 Typical Check Valve
NOTE:
Picture of the check valve is only intended to show an example
of a common check valve installation. It may not represent your specific
unit, check valve size, location or orientation.
The check valve will prevent flow from the condenser to the compressor during the off cycle.
The evaporator section ships with a nitrogen holding charge. Do not vent the evaporator until all
refrigerant piping is in place, ready for connection to the evaporator and condenser. The
discharge, suction and liquid lines need to be refrigerant grade copper and in accordance with
local code. All refrigeration piping should be installed with high temperature brazed joints. When
brazing, a supply of nitrogen gas needs to be fed through the refrigerant lines. Be sure to open
the other end of the refrigerant line to allow the nitrogen to bleed off and not pressurize the
piping. Prevailing good refrigeration practices should be employed for piping support, leak
testing, dehydration and charging the refrigerant circuits. During the installation, the lines should
be capped off and filled with dry nitrogen at the end of each day
’s work or until the system is
completed and sealed.
Data Aire recommends a silver/phosphorus/copper alloy with 5 to 15% silver be used to braze
the refrigerant line sets to the indoor and outdoor units. Nitrogen needs to be flowing through
the lines to eliminate carbon deposit build-up on the inside of the joints. Carbon could
contaminate the refrigerant and restrict the metering device.
Piping must be supported within
18” (457 mm) of the inlet and outlet connections external to the
unit. Internal to the unit, the inlet connection is located on the top header of all units. The
discharge outlet is located at the bottom of the header.