Carrier 50PTH, PTV specifications Refrigerant Charging, Air Coil Fan Motor Removal, Troubleshooting

FILL CONDENSER WITH CLEANING SOLUTION. DO NOT ADD SOLUTION MORE RAPIDLY THAN VENT CAN EXHAUST GASES CAUSED BY CHEMICAL ACTION.

VENT

PIPE

3’ TO 4’

PAIL

FUNNEL

1”

PIPE

5’ APPROX

CONDENSER

Refrigerant Charging

WARNING

To prevent personal injury, wear safety glasses and gloves when handling refrigerant. Do not overcharge system — this can cause compressor flooding.

NOTE: Do not vent or depressurize unit refrigerant to atmo- sphere. Remove and recover refrigerant following accepted practices.

Air Coil Fan Motor Removal

CAUTION

Before attempting to remove fan motors or motor mounts, place a piece of plywood over evaporator coils to prevent coil damage.

PAIL

Fig. 35 — Gravity Flow Method

Disconnect motor power wires from motor terminals before motor is removed from unit.

1.	Shut off unit main power supply.
2.	Loosen bolts on mounting bracket so that fan belt can be

PUMP PRIMING CONN.

SUCTION

PUMP

SUPPORT

TANK

FINE MESH

SCREEN

GAS VENT

GLOBE

VALVES

SUPPLY

1” PIPE

CONDENSER

REMOVE WATER

REGULATING VALVE

RETURN

removed.

3. Loosen and remove the 2 motor mounting bracket bolts

on left side of bracket.

Slide motor/bracket assembly to extreme right and lift out through space between fan scroll and side frame. Rest motor on a high platform such as a step ladder. Do not allow motor to hang by its power wires.

Replacing the WSHP Open Controller’s Bat-

tery — The WSHP Open controller’s 10-year lithium CR2032 battery provides a minimum of 10,000 hours of data retention during power outages.

NOTE: Power must be ON to the WSHP Open controller when replacing the battery, or the date, time and trend data will be lost.

Fig. 36 — Forced Circulation Method

Checking System Charge — Units are shipped with full operating charge. If recharging is necessary:

1.Insert thermometer bulb in insulating rubber sleeve on liquid line near filter drier. Use a digital thermometer for all temperature measurements. DO NOT use a mercury or dial-type thermometer.

2.Connect pressure gage to discharge line near compressor.

3.After unit conditions have stabilized, read head pressure on discharge line gage.

NOTE: Operate unit a minimum of 15 minutes before checking charge.

4.From standard field-supplied Pressure-Temperature chart for R-410A refrigerant, find equivalent saturated con- densing temperature.

5.Read liquid line temperature on thermometer; then subtract from saturated condensing temperature. The dif- ference equals subcooling temperature.

6.Compare the subcooling temperature with the normal temperature listed in Tables 20-23. If the measured liquid line temperature does not agree with the required liquid line temperature, ADD refrigerant to raise the tempera- ture or REMOVE refrigerant (using standard practices) to lower the temperature (allow a tolerance of ± 3° F).

1.Remove the battery from the controller, making note of the battery's polarity.

2.Insert the new battery, matching the battery's polarity with the polarity indicated on the WSHP Open controller.

TROUBLESHOOTING

When troubleshooting problems with a WSHP, consider the following:

Thermistor — A thermistor may be required for single- phase units where starting the unit is a problem due to low voltage. See Fig. 37 for thermistor nominal resistance.

Control Sensors — The control system employs 2 nom- inal 10,000 ohm thermistors (FP1 and FP2) that are used for freeze protection. Be sure FP1 is located in the discharge fluid and FP2 is located in the air discharge. See Fig. 38.

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