Fedders Split System Air Conditioner Model, Electrical Connections cont, Braze joints, Evacuation

Model

Electrical Connections (cont.)

Connect Control Wiring

1.Route 24 volt control wires through control wiring grommet and connect leads to control wiring.

2.Use No. 18 AWG color coded, insulated wire. If thermostat is located more than 100 ft. from unit, as measured along the control voltage wires, use No. 16 AWG wire to avoid excessive voltage drop.

3.All wiring must be NEC Class 1 and must be separated from incoming power leads. Use furnace transformer, fan coil transformer, or accessory transformer for control power.

Note: Use of available 24 volt accessories may exceed the minimum power requirement. Determine total transformer load and increase the transformer capacity or split the load with an accessory transformer as required.

Final wiring check

Check factory wiring and field wire connections to ensure terminations are secured properly. Check wire routing to ensure wires are not in contact with tubing, sheet metal, etc.

SERVICE VALVE CONNECTIONS

Braze joints

1.Remove the valve core from the schrader port. Wrap a quenching cloth around the service valve. Clean and flux the joint and braze with brazing rod containing at least 10% silver (such as silphos type brazing rod). DO NOT USE SOFT SOLDER. Replace the schrader valve core after brazing has cooled.

2.Leak-check all braze joints at approximately 80 psi pressure, purge, and evacuate the lines.

WARNING

DO NOT USE AIR TO LEAK-CHECK BRAZE JOINTS. DRY NITROGEN SHOULD BE USED TO LEAK-CHECK.

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Torch	Service
	valve
Brazing rod
	Quenching Cloth

WARNING

ALWAYS HAVE A FIRE EXTINGUISHER AVAILABLE WHEN WORKING WITH AN OPEN FLAME.

ALWAYS USE SAFETY GLASSES, PROTECTIVE CLOTHING, AND WORK GLOVES.

Evacuation

The outdoor unit is factory charged. Evacuation is necessary on the uncharged portions of the total system. Purge the system with dry nitrogen. Then connect a vacuum pump and a vacuum gage capable of accurately measuring below 1,000 microns vacuum depth. The deep vacuum method is the most positive way of assuring a system is free of air and liquid water.

WARNING

IF THE INSTALLER IS MAKING UP HIS OWN LINE SETS, HE MUST MAKE SURE THE TUBING IS CLEAN OF ANY IMPURITIES OR MOISTURE.

Opening the Service Valve (Step Valve)

NOTE: This is not a back-seating valve.

1.Remove the valve cap using an adjustable wrench.

2.Open the valve by inserting a hex wrench (3/16" for the liquid line, 5/16" for the vapor line) into the stem and back out counter-clockwise until the valve stem just touches the retaining ring. Do not over tighten.

3.Replace the valve cap finger-tight, then tighten an additional 1/12 turn or 1/2 hex flat. A metal-to-metal seal is now complete.

115
	Schrader
	valve port
Remove cap	Open valve	Replace cap

Opening the Service Valve (Straight Valve)

NOTE: This is not a back-seating valve.

Open the valve by using an adjustable wrench to turn the adjusting flange 1/4 turn counter-clockwise. The flange will come to a stop and the seal is now complete.

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Adjusting flange

Open valve

3