FloAire Modular Packaged Unit - Manual (Page 13)

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If the superheat is too low, and an adjustable-type valve is supplied, the superheat can be increased by
turning the adjustment stem in a clockwise direction. It's a good practice to wait for 15 to 20 minutes after
adjusting the valve, to allow for the system to balance out before determining the effect of the adjustment.
If the superheat is too high, it can be lowered by turning the stem in a counter-clockwise direction.
To adjust the superheat, first remove the bottom cap from the TXV. Next, turn the adjustment screw
clockwise to increase superheat or counterclockwise to decrease superheat. Adjust about ½ turn at a
time and allow system to stabilize. Once proper superheat is set, replace the TXV cap.
Checking Heating Mode for Units with Heat Pumps
Refrigerant charge in heat pumps should be checked while the unit is in cooling mode with the same
Subcooling and Superheat method described above. However, it is also important to check heating mode
to make sure the unit is operating properly.
Attach the refrigerant gauges to the heat pump with the
red high pressure line connected to the suction line and
the blue low pressure line connected to the middle access
port as shown below.
Turn the heating thermostat up until the first heat pump
comes on. Allow the heat pump to run for 15 minutes and
check the high side pressure. The pressure should not
exceed the maximum operating pressure listed on the unit
name plate. If the pressure is high, refrigerant will need to
be removed. Removing refrigerant will also affect cooling
mode subcool and superheat, so they will need to be
checked again also.