AAON F-060 - Manual (Page 22)

22
Table 7 - Acceptable Air-Cooled
Refrigeration Circuit Values
Sub-
cooling
(°F)
Superheat
(°F)
Sub-cooling
with Hot
Gas Reheat
(°F)
Air-
Cooled
Condenser
12-18* 8-15** 15-22*
* Sub-cooling must be increased by 2°F per
20 feet of vertical liquid line rise for R-
410A
** Superheat will increase with long suction
line runs.
Correct an overcharged system by reducing
the amount of refrigerant in the system to
lower the sub-cooling.
The system is undercharged if:
1. The superheat is too high and
2. The sub-cooling is too low.
Correct an undercharged system by adding
refrigerant to the system to reduce superheat
and raise sub-cooling.
If the sub-cooling is correct and the
superheat is too high, the TXV may need
adjustment to correct the superheat.
Elevation Limitations
See Table 8 for rise and run limitations. All
lengths listed are in equivalent feet. An
equivalent foot of the line includes the
pressure drop of all valves, components,
fittings and other pipes in the sections.
Evaporator Coil
The indoor coil is pressurized. The copper
caps must be punctured to permit a gradual
escape of the pressure prior to unsweating
those caps. Immediately couple the tubing to
the indoor unit to avoid exposing the coils to
moisture. A properly sized filter drier is
furnished in the condenser. When making
solder connections, make sure dry nitrogen
flows through the lines, when heating the
copper, to prevent oxidization inside of the
copper.
DO NOT OVERCHARGE!
Refrigerant overcharging leads to
excess refrigerant in the condenser
coils resulting in elevated compressor
discharge pressure.
CAUTION
Evaporator coils are shipped under
high pressure. Use extreme care and
follow the installation instructions
provided with the evaporator coil to
avoid personal injury.
CAUTION