Data Aire gForce Ultra - 8. Controls; 8.1 dap4 Microprocessor Control Panel

gForce Ultra IOM
53
Heat Exchanger Phase Check
GHRC Air-Cooled Heat Exchanger Phase Check
Air-cooled GHRC condensers and GHRU condensing unit heat exchangers (with axial EC fan motors)
are only offered in three phase voltages and the individual EC fan motors will only operate in one
direction but the rotation of the compressor on GHRU units must be checked. See the GHRC Air-
Cooled Condensers Installation, Operations and Maintenance Manual for additional information
regarding this type of heat exchanger.
DARC Air-Cooled Heat Exchangers Phase Check
The DARC heat exchangers have standard prop-type fan blades with direct-drive AC motors. See
the DARC air-cooled heat exchanger Installation, Operations and Maintenance Manual for proper
phase check procedures.
Line Set Charge Calculations
1. Since most of the refrigerant weight is in liquid form in the liquid line, refrigerant in the hot
gas line and suction line is ignored in the charging calculation.
2. Calculate the total of the liquid line run, then multiply the equivalent feet of line based on the
line size by the correct multiplier to get the refrigerant weight needed for the line-set.
Table 10 Liquid Line Multiplier
Liquid Line Nominal
Size (inches)
Liquid Line OD
(inches)
R-410A Multiplier
3/8
1/2
0.068
1/2
5/8
0.109
5/8
3/4
0.157
3/4
7/8
0.243
1
1-1/8
0.387
Note: Charge Weight is calculated at 77F (25C).
Example: If the liquid line of an R-410A system is 150 feet of 1-1/8" OD tube, then
multiply: 150 * 0.387 = 57 lbs.
Example: For a GUAX-125XX (37.5 + 57 lbs.) * 0.80 = 75.6 lbs.
Component Functional Test
Confirm each component operates and is functional by using the dap4, MENU I – MANUAL CONTROL
(Service Level). See dap4 User Manual for details.