Low Voltage Connections

Several combinations of low voltage schemes are available, depending on the presence of a heat kit and whether the heat kit is single-stage or multi-staging. The low voltage con- nections are determined by whether the outdoor unit is a con- denser or heat pump. The 24V-control voltage connects the air handler to the room thermostat and condenser. Low volt- age wiring is to be copper conductors. A minimum of 18AWG must be used for installations up to 50’ and 16AWG for in- stallations over 50’. Low voltage wiring can be connected through the top of the cabinet or either side. See the “Ther- mostat Wiring” section of this manual for typical low voltage wiring connections.

Refrigerant Lines

This product is factory-shipped under pressure. Follow these instructions to prevent injury.

A quenching cloth is strongly recommended to prevent scorching or marring of the equipment finish when welding close to the painted surfaces. Use brazing alloy of 5% minimum silver content.

Tubing Preparation

All cut ends are to be round, burr free, and clean. Failure to follow this practice increases the chances for refrigerant leaks. The suction line is spun closed and requires pipe cutters to remove the closed end.

Post Brazing

Quench all welded joints with water or a wet rag.

Piping Size

For the correct tubing size, follow the specification for the condenser/heat pump.

CAUTION

Applying too much heat to any tube can melt the tube. Torch heat required to braze tubes of various sizes must be proportional to the size of the tube. Service personnel must use the appropriate heat level for the size of the tube being brazed.

Special Instructions

This coil comes equipped with a check style flowrator for re- frigerant management. For most installations with matching applications, no change to the flowrator piston is required. However, in mix-matched applications, a flowrator piston change may be required. See the Goodman® piston kit chart or consult your local distributor for details regarding mix- matched piston sizing. If the mix-match application requires a different piston size, change the piston in the flowrator on the indoor coil before installing the coil and follow the proce- dure shown below.

IMPORTANT NOTE: Torch heat required to braze tubes of various sizes is proportional to the size of the tube. Tubes of smaller size require less heat to bring the tube to brazing temperature before adding brazing alloy. Applying too much heat to any tube can melt the tube. Service personnel must use the appropriate heat level for the size of the tube being brazed.

NOTE: The use of a heat shield when brazing is recommended to avoid burning the serial plate or the finish on the unit. Heat trap or wet rags should be used to protect heat sensitive components such as service valves and TXV valves.

1.Loosen the 13/16 nut 1 TURN ONLY to allow high pres- sure tracer gas to escape. No gas indicates a possible leak.

2.After the gas has escaped, remove the nut and discard the black or brass cap.

3.Remove the check piston to verify it is correct and then replace the piston. See piston kit chart in instructions.

4.Use a tube cutter to remove the spin closure on the suction line.

5.Remove the tailpiece clamped to the exterior and slide the 13/16 nut into place.

6.Braze tailpiece to the line set liquid tube.

PLASTIC or BRASS CAP

13/16” NUT

TAILPIECE

WHITE

PISTON

TEFLON SEAL

 

Figure 1

7.Insert the suction line into the connection, slide the in- sulation and the rubber grommet at least 18" away from the braze joint. Braze suction line.

8.AFTER THE TAILPIECE HAS COOLED, confirm posi- tion of the white Teflon® seal and hand tighten the 13/16 nut.

9.Torque the 13/16 nut to 7-25 ft-lbs. or tighten 1/6 turn.

Excessive torque can cause orifices to stick. Use the proper torque settings when tightening orifices.

10. Replace suction line grommet and insulation.

SUCTION LINE

WITH SPIN CLOSURE

RUBBER

GROMMET

Figure 2

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Goodman Mfg IO-431, ASPF Air Handlers operating instructions Refrigerant Lines, Low Voltage Connections