Servicing Units Delivered Void of Charge
If the outdoor unit is void of refrigerant, clean the system using the procedure described below.
1.Leak check system using procedure outlined on Page 16.
2.Evacuate the system using procedure outlined on Page 18.
3.Use nitrogen to break the vacuum and install a new filter drier in the system.
4.Evacuate the system again using procedure outlined on Page 18.
5.Weigh in refrigerant using procedure outlined in Figure 14.
6.Monitor the system to determine the amount of moisture remaining in the oil. It may be necessary to replace the filter drier several times to achieve the required dryness level. If system dryness is not verified, the compressor will fail in the future.
Unit Start−Up
IMPORTANT
If unit is equipped with a crankcase heater, it should be energized 24 hours before unit start−up to prevent compressor damage as a result of slugging.
1.Rotate fan to check for binding.
2.Inspect all factory− and field−installed wiring for loose connections.
3.After evacuation is complete, open both the liquid and vapor line service valves to release the refrigerant charge contained in outdoor unit into the system.
4.Replace the stem caps and tighten to the value listed in Table 1.
5.Check voltage supply at the disconnect switch. The voltage must be within the range listed on the unit’s nameplate. If not, do not start the equipment until you have consulted with the power company and the voltage condition has been corrected.
6.Set the thermostat for a cooling demand. Turn on power to the indoor indoor unit and close the outdoor unit disconnect switch to start the unit.
7.Recheck voltage while the unit is running. Power must be within range shown on the nameplate.
8.Check system for sufficient refrigerant by using the procedures listed under System Charge.
System Refrigerant
This section outlines procedures for:
1.Connecting gauge set for testing and charging;
2.Checking and adjusting indoor airflow;
3.Adding or removing refrigerant.
GAUGE SET
CONNECTIONS FOR TESTING AND CHARGING
MANIFOLD GAUGE SET
LOW HIGH
| SUCTION LINE |
|
B SERVICE PORT |
| |
| CONNECTION |
|
| REFRIGERANT TANK | |
| CHARGE IN | A |
| LIQUID PHASE | |
|
| |
| DIGITAL SCALE | |
D TEMPERATURE | C | |
SENSOR |
| |
|
| |
|
| TO LIQUID |
|
| LINE SERVICE |
|
| VALVE |
OUTDOOR UNIT
VAPOR LINE
SERVICE VALVE
TEMPERATURE SENSOR
(LIQUID LINE)LIQUID LINE SERVICE VALVE
AClose manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging.
BConnect the manifold gauge set’s low pressure side to the suction line service port.
CConnect the manifold gauge set’s high pressure side to the liquid line service port.
DPosition temperature sensor on liquid line near liquid line service port.
Figure 11. Gauge Set Setup and Connections
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