Do not leave system open to atmosphere any longer than minimum required for installation. POE oil in compressor is extremely susceptible to moisture absorption. Always keep ends of tubing sealed during installation.
If ANY refrigerant tubing is buried, provide
LIQUID
SERVICE
VALVE
To prevent damage to unit or service valves, observe the following:
•Use a brazing shield.
•Wrap service valves with wet cloth or use a heat sink material.
Outdoor units may be connected to indoor section using accessory tubing package or
Refer to Table 1 for field tubing diameters. Refer to Table 2 for accessory requirements.
Do not bury lines over 36 in. long.
If refrigerant tubes or indoor coil are exposed to atmosphere, they must be evacuated to 500 microns to eliminate contamination and moisture in the system.
Table
Recommended Liquid and Vapor Tube
Diameters (In.)
UNIT | LIQUID | VAPOR | VAPOR | ||||
SIZE | Connection | Tube | Connection | Tube | Connection | Tube | |
Diameter | Diameter | Diameter | Diameter | Diameter | Diameter | ||
| |||||||
024 | 3/8 | 3/8 | 5/8 | 5/8 | 5/8 | 3/4 | |
|
|
|
|
|
|
| |
036 | 3/8 | 3/8 | 3/4 | 3/4 | 3/4 | 7/8 | |
|
|
|
|
|
|
| |
037, 048 | 3/8 | 3/8 | 7/8 | 7/8 | 7/8 | 7/8 | |
060 | 3/8 | 3/8 | 7/8 | 7/8 | |||
|
|
|
|
|
|
| |
Notes:
1.Tube diameters are for lengths up to 50 equivalent ft.
2.Do not apply capillary tube indoor coils to these units.
OUTDOOR UNIT CONNECTED TO FACTORY-APPROVED INDOOR UNIT
Outdoor unit contains correct system refrigerant charge for opera- tion with indoor unit of same size when connected by 15 ft of
Installation of filter drier in liquid line is required.
INSTALL LIQUID-LINE FILTER DRIER
Installation of filter drier in liquid line is required. Refer to Fig. 7 and install filter drier as follows:
A01215
Fig. 7—Filter Drier with Sweat Adapter Tube and
Liquid Tube
1.Braze
2.Braze filter drier between connector tube and liquid tube to indoor coil. Flow arrow must point toward indoor coil.
REFRIGERANT TUBING
Connect vapor tube to fitting on outdoor unit vapor service valves. Connect liquid tube to filter drier. (See Fig. 7and Table 1.)
SWEAT CONNECTION
Service valves are closed from factory and ready for brazing. After wrapping service valve and filter drier with a wet cloth, braze sweat connections using industry accepted methods and materials. Do not use soft solder (materials which melt below 800°F). Consult local code requirements. Refrigerant tubing and indoor coil are now ready for leak testing. This check should include all field and factory joints.
LEAK CHECKING
Leak test all joints in indoor, outdoor, and refrigerant tubing.
EVACUATE REFRIGERANT TUBING AND INDOOR COIL
Never use the system compressor as a vacuum pump.
Refrigerant tubes and indoor coil should be evacuated to 500 microns. Always break a vacuum with dry nitrogen.
Deep Vacuum Method
The deep vacuum method requires a vacuum pump capable of pulling a minimum vacuum of 500 microns and a vacuum gage or thermistor capable of accurately measuring this vacuum depth. The deep vacuum method is the most positive way of assuring a system is free of air and liquid water. (See Fig. 8.)
Triple Evacuation Method
The triple evacuation method should only be used when vacuum pump is capable of pumping down to 28 in. of mercury and system does not contain any liquid water. Refer to Fig. 9 and proceed as follows:
1.Pump system down to 28 in. of mercury and allow pump to continue operating for an additional 15 minutes.
2.Close service valves and shut off vacuum pump.
3.Connect a nitrogen cylinder and regulator to system and open until system pressure is 2 psig.
4.Close service valve and allow system to stand for 1 hr. During this time, dry nitrogen will be able to diffuse throughout the system, absorbing moisture.
4