Charging
The XC21 unit is factory−charged with enough HFC−410A refrigerant to accommodate a 15−foot length of refrigerant
piping. Charge should be checked and adjusted using the
tables provided on the charging procedure sticker on the
unit access panel. Detailed information is given in the
XC21 Installation and Service Procedures manual, which is available on DaveNet.
Start−Up Checklists
TWO−STAGE COMPRESSOR PERFORMANCE
Use this procedure to verify part- and
eration of the
IMPORTANT !
This performance check is ONLY valid on systems that have clean indoor and outdoor coils, proper airflow over coils, and correct system refrigerant charge. All components in the system must be functioning properly to correctly perform compressor operational check. (Accurate measurements are critical to this test as indoor system loading and outdoor ambient can affect variations between low and high capacity readings).
TOOLS REQUIRED
SRefrigeration gauge set
SDigital volt/amp meter
SElectronic temperature thermometer
S
PROCEDURE
1. Turn main power OFF to outdoor unit.
2.Adjust room thermostat set point 5ºF above (heating operation) or 5ºF below (cooling operation) the room temperature.
3.Remove control access panel. Install refrigeration gauges on unit. Attach the amp meter to the common (black wire) wire of the compressor harness. Attach thermometer to discharge line as close as possible to the compressor.
4.Turn toggle switch OFF. Install switch in series with Y2 wire from room thermostat. (See note ** in the Field Operational Checklist on page 17).
5.Cycle main power ON.
6.Allow pressures and temperatures to stabilize before taking any reading (may take up to 10 minutes).
7.Record all of the readings for the Y1 demand.
8.Close switch to energize Y2 demand. Verify power is going to compressor solenoid (see note ** in the Field Operational Checklist on page 17).
9.Allow pressures and temperatures to stabilize before taking any reading (may take up to 10 minutes).
10.Record all of the readings with the Y1 and Y2 demand.
11.If temperatures and pressures change in the direction noted in chart, the compressor is properly modulating from low to high capacity. (If no amperage, pressures or temperature readings change when this test is per- formed, the compressor is not switching between low and high capacity and replacement is necessary.)
12.After testing is complete, return unit to original set up.
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