Service and Weigh In Refrigerant for Outdoor Units Delivered Void of Charge
The following procedures are only required if it has been determine that the new outdoor unit is void of charge. Skip to the next section if refrigerant charge is present.
LEAK CHECK, REPAIR AND EVACUATE
If the outdoor unit is void of refrigerant, clean the system using the procedure described below.
1.Leak check system using procedures provided on page 16. Repair any leaks discovered during leak test.
2.Evacuate the system using procedure provided in figure 13.
3.Use nitrogen to break the vacuum and install a new filter drier in the system.
4.Evacuate the system again using procedure in figure 12.
CONNECT MANIFOLD GAUGE SET AND WEIGH IN CHARGE
After the evacuation procedure, reconnect the manifold gauge set as illustrated in figure 21.
NOTE − Temperature sensor illustrated in figure 21 is not required for initial system weigh in charging.
1.Close manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging.
2.Connect the manifold gauge set’s low pressure side to the true suction port.
3.Connect the manifold gauge set’s high pressure side to the liquid line service port.
4.Connect the center hose of the gauge set to a cylinder of HFC−410A and purge the hose. Then, place the cylinder upside down on a scale.
5.Check that fan rotates freely.
6.Inspect all factory− and field−installed wiring for loose connections.
7.Open the high side manifold gauge valve and weigh in liquid refrigerant. Use figure 20 in calculating the correct weigh−in charge.
8.Close manifold gauge valves.
9.Monitor the system to determine the amount of moisture remaining in the oil. It may be necessary to replace the bi−flow filter drier several times to achieve the required dryness level. If system dryness is not verified, the compressor will fail in the future.
10.Continue to Optimizing System Refrigerant Charge on page 26 to optimize the system charge using subcooling method.
WEIGH−IN CHARGING
CALCULATING SYSTEM CHARGE FOR OUTDOOR UNIT VOID OF CHARGE
If the system is void of refrigerant, first, locate and repair any leaks and then weigh in the refrigerant charge into the unit. To calculate the total refrigerant charge:
Amount specified on |
| Adjust amount. for variation in line set | Additional charge specified per indoor | Total Charge | ||||||||||
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| length listed on line set length table below. | unit match listed on page 28. |
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| Refrigerant Charge per Line Set Length |
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| LIQUID LINE SET DIAMETER | OUNCES PER 5 FEET (G PER 1.5 M) ADJUST FROM 15 FEET |
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| (4.6 M) LINE SET* |
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| 3/8" (9.5 MM) |
| 3 OUNCE PER 5’ (85 G PER 1.5 M) |
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| *If line length is greater than 15 ft. (4.6 m), add this amount. If line length is less than 15 ft. (4.6 m), subtract | |||||||||||
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NOTE |
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of the liquid line or when pressure drop is equal to or greater than 20 psig. |
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NOTE . Go to actual nameplate on outdoor unit for charge information.
Figure 20. Using HFC−410A Weigh In Method
Page 24