Data Aire gForce Ultra, Installation, Operation And Maintenance Manual

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2.7.1 Air Cooled Unit Piping
Air-cooled unit piping is crimped and brazed closed from the factory and contains a nitrogen holding
charge. Each installation requires field-supplied refrigerant piping to a condenser.
Refer to section RECOMMENDED LINE SIZING charts in section 2.7.4 for a guideline on sizing
refrigerant lines. The ultimate responsibility for line size selection is that of the installing contractor or
design engineer. Data Aire does not assume this responsibility. The chart covers distances up to 200
equivalent feet (61 m). For installations beyond this distance, consult ASHRAE or similar references.
NOTE:
Standard piping practice must be used to ensure proper oil return
and efficient operation. The interconnecting lines to the remote air cooled
condenser or condensing unit must be installed by a qualified refrigeration
mechanic.
2.7.2 Discharge Lines
Discharge lines, also called hot gas lines, should be trap
ped at the top (inverted) and bottom as well
as every 15 to 20 feet (4.6 to 6.1 m) of vertical rise. Discharge check valves are required on all instal-
lations, especially those where there are long pipe runs or cold climates. For air-cooled units built after
3/14/2017, the discharge check valves are already installed inside the evaporator section and do not
need to be installed external to the unit. For units built before this date, the check valves must be field
supplied and installed externally to the evaporator section. If there is doubt as to whether or not the
check valve is already installed in the unit, look for it on the hot gas line close to the exit point of the unit
(see example picture below). The externally installed check valve should be placed from six (6) to ten
(10) feet (1.8 to 3.1 m) from the compressor.
Note: Picture 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.