OUTDOOR UNIT | DISTRIBUTOR |
|
| NOTE − ARROWS INDICATE DIRECTION | |
|
| |
|
| OF REFRIGERANT FLOW |
| REVERSING VALVE | |
CHECK / EXPANSION |
|
|
VALVE |
|
|
| OUTDOOR |
|
| COIL |
|
BI−FLOW FILTER / DRIER |
| INDOOR UNIT |
|
| |
| MUFFLER |
|
| TRUE SUCTION | VAPOR |
| PORT | |
| SERVICE | |
|
| |
|
| PORT |
LIQUID LINE | COMPRESSOR |
|
SERVICE PORT |
| |
|
| |
|
| CHECK / EXPANSION VALVE |
INDOOR
NOTE − Use gauge ports on vapor line valve and liquid valve for evacuating refrigerant lines andCOIL indoor coil. Use true suction port to measure vapor pressure during charging.
Figure 21. Heat Pump Cooling Cycle
Optimizing System Refrigerant Charge
This section provides instructions on optimizing the system charge. This section includes:
SOptimizing procedure
SAdjusting indoor airflow
SUsing subcooling method
SApproved matched components, targeted subcooling (SC) values and add charge values
efficiency. Make any air flow adjustments before continuing with the optimizing procedure.
5.Use subcooling method to optimize the system charge (see figure 23). Adjust charge as necessary.
ADJUSTING INDOOR AIRFLOW
Heating Mode Indoor Airflow Check
(Only use when indoor unit has electric heat)
SNormal operating pressures
STemperature pressures
OPTIMIZING PROCEDURE
1.Move the low−side manifold gauge hose from the vapor line service valve to the true suction port (see figure 19).
2.Set the thermostat for either cooling or heating demand. Turn on power to the indoor unit and close the outdoor unit disconnect switch to start the unit.
3.Allow unit to run for five minutes to allow pressures to stabilize.
4.Check the airflow as instructed under Adjusting Indoor Airflow to verify or adjust indoor airflow for maximum
Indoor blower airflow (CFM) may be calculated by energizing electric heat and measuring:
STemperature rise between the return air and supply air temperatures at the indoor coil blower unit,
SMeasuring voltage supplied to the unit,
SMeasuring amperage being drawn by the heat unit(s).
Then, apply the measurements taken in the following formula to determine CFM:
Amps x Volts x 3.41
CFM =
1.08 x Temperature rise (F)
Cooling Mode Indoor Airflow Check
Check airflow using the Delta−T (DT) process using figure 22.
Page 25
XP14 SERIES
