48
An out of phase fixed speed scroll compressor will draw relatively low amps and both suction and
discharge pressures will remain nearly equal. If necessary, reverse any two of the three input line
voltage wires at the line voltage field connection point to change the compressor rotation.
Units shipped from the factory are run tested to ensure the compressor rotation is consistent with
evaporator fan motor. However, a field changeout of a compressor may require checking proper phase.
Heat Exchanger Phase Check
GHRC Air-Cooled Heat Exchanger Phase Check
Air-cooled GHRC condensers and GHRU condensing unit heat exchangers are only offered in three
phase voltages and the individual axial 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 Heat Exchangers Phase Check
See the DARC Air-Cooled Condensers 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 the line based on
the line size by the correct multiplier to get the refrigerant weight needed for the line-set.
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 = 57.06 lbs.
Example: model DAPA-2.5XX (6.0 + 57.06 lbs.) * 0.80 = 50.5 lbs.
To Next Page
Loading...