Data Aire gForce Ultra Installation, Operation And Maintenance Manual page 40

Example: If the liquid line of an R-410A system is 150ft of 1-1/8" pipe, then multiply
150 * 0.38 = 57lbs
Step 3: Add refrigerant weights from step 1 and 2 together and multiply by .80 to get the
starting charge.
Example: model GUAX-125XX (37.5 + 57 lbs.) *.80 = 75.6 lbs.
2.
Next connect the refrigerant tank to the refrigerant manifold gauge set and make sure
the manifold gauge set is properly purged.
3. Then from a vacuum, slowly open the high side liquid line valve on the refrigerant
manifold gauge to feed liquid refrigerant through the high side.
4. Add the amount of refrigerant weight per tables, slowly open the high side liquid line valve
on the refrigerant manifold gauge to feed liquid refrigerant through the high side.
At this point there will be approximately 70-80% of the total charge in the system. It is likely that more
refrigerant will be required to complete the charging procedure. Close the valve on the refrigerant mani-
fold gauge set.
WARNING:
energized for a minimum of 12 hours to reduce the possibility of liquid slug-
ging on start-up. Failure to energize the crankcase heater could result in
compressor damage. If the system is charged from a vacuum, the preheat-
ing of the compressor is not necessary.
The variable speed compressor requires a little more care while charging. All unit safeties must be
active while charging the compressor. In order to ensure this, manual bypass switches on the Manual
Override Board MUST NOT be used. Instead the unit must be started in the normal operating mode
based on a call for cooling required by the dap4 controller once an initial charge has been added to
the circuit. Before starting the system, make sure pressure gauges are hooked up and pressure read-
ings are aligned with EEV reading. For dual circuit units, remove the fixed speed compressor's fuses
to prevent it from starting.
If the unit is in OFFbyKEY position, hold the "Esc" button for 5 seconds to start the system via the dap4
controller. Next, controlled temperature needs to be higher than temperature setpoint for the compres-
sor to start. To do this, press the "Menu" button where you will be prompted to enter in the service pass-
word before continuing. The default service password is "0000" By utilizing the arrow keys, scroll up
or down to menu "H. Calibrate Sensors" and press ENTER. If the system is being controlled from the
return air temperature sensors simply scroll down to the "Return Air Temp Sensor" menu and press EN-
TER to move the cursor to the offset value. Use the up and down arrow keys to change the offset value
to +20 °F. Then press ENTER to set the offset. This should allow the temperature to be much higher
than the temperature setpoint and the variable speed compressor will start and run at a full speed of
6000 RPM (or 200Hz). If controlling with discharge air temperature sensor follow the same steps but
use the "Discharge Air Temp Sensor" menu.
Before starting a compressor, the crankcase heater should be
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