52S
SERIES
FAN MOTOR
The fan motor is a permanent split capacitor (PSC) type motor. This motor is common in
The 52S series fan motor has a motor shaft extended through both ends. It powers both the indoor and the out- door fans. It has permanently sealed bearings that re- quire no lubrication. There are many different fan motor models, but they typically are 2 speed or 3 speed and in 2 voltage categories, 208/230 and 265 volts.
FIGURE 62 Ð TWO-SPEED, PERMANENT
SPLIT CAPACITOR MOTOR (PSC)
FAN MOTOR TROUBLESHOOTING
Refer to Figure 63 for a basic fan motor troubleshooting chart.
TOOLS NEEDED Ð The following list includes rec- ommended tools and devices for working on the fan motor of 52S units.
Gloves
Safety Glasses
Regular and Phillips Head Screw Drivers
Small Adjustable Wrench
Allen Wrench Set (extra length)
Channel Lock Pliers
Before cleaning, servicing, performing maintenance or removing the chassis from the wall sleeve, discon- nect all power to the unit to avoid the possibility of electrical shock and personal injury. Only trained and quali®ed service personnel should perform installation and service procedures on these units. Untrained personnel may perform basic maintenance tasks such as cleaning and replacing ®lters. Refer to GENERAL DISASSEMBLY section of this manual for proper procedures to disconnect power to 52S units.
The Manufacturer reserves the right to discontinue, or change at any time, speci®cations or designs without notice and without incurring obligations.
Consider the following safety issues:
·Prior to performing any service or maintenance on electrical equipment you must Disconnect All
Power.
·New and unfamiliar tasks should be performed under the supervision of an experienced service technician.
·Personal protective equipment, such as safety glasses and work gloves, should be worn.
·The ¯oor around the work area should be clean and free of debris.
·Make sure tools are the correct tools for the job, and that they are working properly and in good condition.
·The 52S unit may weigh up to 150 pounds. Use a lift- ing device or ask for assistance if the unit must be moved.
BASIC FAN MOTOR ELECTRICAL TESTS
There are 2 basic electrical tests for PSC fan motors that will determine the electrical state of the motor. The ®rst test requires checking the electrical resistance be- tween the motor windings. The second test requires checking the electrical resistance between the motor windings and ground. These tests may be accomplished by performing the following steps:
1.DISCONNECT ALL POWER TO UNIT.
2.Remove the unit from the sleeve and open the con- trol box as detailed in the GENERAL DISASSEM- BLY section.
3.Label and disconnect the fan motor wires from the push button switch and capacitor as shown in Figure 5.
4.Measure and record the resistance between the black wire and each of the other wires. Make sure the mo- tor is cool before attempting to measure resistance.
The internal thermostat of the motor may be electri- cally open and will not close until the motor cools. See Figure 64 for typical motor winding resistance measurements. The resistance values in the table are approximate. Values that are within 10% of those listed are acceptable. If the motor in your model is not listed, ®nd a motor of similar horsepower and voltage on the chart and compare it to the resistance measurements of your motor.
5.Measure the resistance of each of the motor wires to the motor casing. The resistance should be in®nite. Make sure the motor is cool before attempting to mea- sure resistance. The internal thermostat of the mo- tor may be electrically open and will not close until the motor cools. A motor that has measurable re- sistance to ground is shorted to ground and must be replaced.
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