Carrier 38EYA Tighten Refrigerant Tubing and Filter Drier, Sweat Connection, Leak Checking

Table 2—Accessory Usage

	REQUIRED FOR LOW-AMBIENT	REQUIRED FOR LONG-LINE
ACCESSORY	APPLICATIONS	APPLICATIONS*
	(BELOW 55°F)	(OVER 50 FT)
Crankcase Heater	Yes	Yes
Evaporator Freeze Thermostat	Yes	No
Compressor Start Assist—Capacitor and Relay	Yes	Yes
Puron® Low-Ambient Pressure Switch	Yes	No
Wind Baffle	See Low-Ambient Instructions	No
Support Feet	Recommended	No
Hard Shutoff TXV	Yes†	Yes†
Liquid-Line Solenoid Valve for Heating	No	See Long-Line
		Application Guideline

*For tubing line sets between 50 and 175 ft, or when vertical difference is greater than 20 ft, refer to Application Guideline and Service Manual — Residential Split-System Air Conditioners and Heat Pumps Using Puron® .

† Required for all applications.

wrench an additional 1/12 turn (15 ft-lb). DO NOT OVER-

TIGHTEN.

REFRIGERANT TUBING AND FILTER DRIER

Installation of filter drier in liquid line is required.

Connect vapor tubing to fittings on outdoor unit vapor service valves. Connect liquid tube to filter drier. (See Table 1 and Fig. 8.) Use refrigerant grade tubing. Connect other end of filter drier to adapter tube on liquid service valve.

SWEAT CONNECTION

To avoid valve damage while brazing, service valves must be wrapped in a heat-sink material such as a wet cloth.

Wrap service valves and filter drier with a wet cloth or heat- sinking material. Braze connections using either silver bearing or non-silver bearing brazing material. Do not use soft solder (materials which melt below 800°F.) Consult local code require- ments.

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 using the recommended deep vacuum method of 500 microns. The alternate triple evacuation method may be used if the procedure outlined below is followed.

IMPORTANT: Never open system under vacuum to atmosphere without first breaking it open with 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. 9.)

Triple Evacuation Method

The triple evacuation method should only be used when vacuum pump is only capable of pumping down to 28 in. of mercury vacuum and system does not contain any liquid water. Refer to Fig. 10 and proceed as follows:

5000
4500
4000						LEAK IN
3500
						SYSTEM
3000
2500
MICRONS2000						VACUUM TIGHT
1500
						TOO WET
1000
						TIGHT
500
						DRY SYSTEM
0	1	2	3	4	5	6	7
			MINUTES
							A95424

Fig. 9—Deep Vacuum Graph

EVACUATE

BREAK VACUUM WITH DRY NITROGEN

WAIT

EVACUATE

BREAK VACUUM WITH DRY NITROGEN

WAIT

EVACUATE

CHECK FOR TIGHT, DRY SYSTEM (IF IT HOLDS DEEP VACUUM)

CHARGE SYSTEM

A95425

Fig. 10—Triple Evacuation Method

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