Carrier Puron 38TZA - System Evacuation and Leak Testing; Evacuate Refrigerant Tubing and Coil; Deep Vacuum Method; Final Tubing Check

SWEAT CONNECTION
To avoid valve damage while brazing, service valves must be
wrapped in a heat-sinking material such as a wet cloth.
Service valves are closed from factory and ready for brazing. After
wrapping service valve and filter drier with a wet cloth, tubing set
can be brazed to service valve and filter drier using either silver
bearing or non-silver bearing brazing material. Consult local code
requirements. Refrigerant tubing and indoor coil are now ready for
leak testing. This check should include all field and factory joints.
EVACUATE REFRIGERANT TUBING AND INDOOR COIL
Never use the system compressor as a vacuum pump.
Refrigerant tubes and indoor coil should be evacuated using the
recommended deep vacuum method of 500 microns. The alternate
triple evacuation method may be used if the procedure outlined
below is followed. Always break a vacuum with dry nitrogen.
Deep Vacuum Method
The deep vacuum method requires a vacuum pump capable of
pulling a vacuum of 500 microns and a vacuum gage 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. 6.)
Table 1—Refrigerant Connections and Recommended Liquid and Vapor Tube Diameters (In.)
UNIT
SIZE
LIQUID VAPOR VAPOR (LONG LINE)
Connection Diameter Tube Diameter Connection Diameter Tube Diameter Connection Diameter Tube Diameter
024 3/8 3/8 5/8 5/8 5/8 3/4
030, 036 3/8 3/8 3/4 3/4 3/4 7/8
042, 048 3/8 3/8 7/8 7/8 7/8 1-1/8
060 3/8 3/8 7/8 1-1/8 7/8 1-1/8
NOTES:
1. Tube diameters are for lengths up to 50 ft. For tubing lengths greater than 50 ft, consult the Application Guideline and Service Manual for Residential Split-System
Air Conditioners and Heat Pumps Using Puron™ Refrigerant.
2. Do not apply capillary tube indoor coils to these units.
Table 2—Accessory Usage
ACCESSORY
REQUIRED FOR
LOW-AMBIENT
APPLICATIONS
(BELOW 55°F)
REQUIRED FOR
LONG-LINE
APPLICATIONS*
(OVER 50 FT)
REQUIRED FOR
SEA COAST
APPLICATIONS
(WITHIN 2 MILES)
Crankcase Heater Yes Yes No
Evaporator Freeze Thermostat Yes No No
Winter Start Control Yes† No No
Accumulator No No No
Compressor Start Assist
Capacitor and Relay
Yes Yes No
Low-Ambient Controller,
MotorMaster® Control,
or
Low-Ambient Pressure Switch
Yes No No
Wind Baffle See Low-Ambient Instructions No No
Coastal Filter No No Yes
Support Feet Recommended No Recommended
Liquid-Line Solenoid Valve
or
Hard Shutoff TXV
No
See Long-Line
Application
Guideline
No
Ball Bearing Fan Motor Yes‡ No No
* For tubing line sets between 50 and 175 ft, refer to the Application Guideline and Service Manual for Residential Split-System Air Conditioners and Heat Pumps using
Puron™ Refrigerant.
† Only when low-pressure switch is used.
‡ Required for Low-Ambient Controller (full modulation feature) and MotorMaster® Control only.
Fig. 5—Liquid-Line Filter Drier
A95509
LIQUID-LINE
FILTER-DRIER
CONNECTOR
TUBE
R
-
4
1
0
A
LIQUID
SERVICE
VALVE
4
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