FAN MOTOR
The fan motor is a permanent split capacitor (PSC) type motor. This motor is common in
The 52C,P series fan motor has a motor shaft extended through both ends. It powers both the indoor and the outdoor fans. It has permanently sealed bearings that require no lubrication. There are many different fan motor models, but they typically are
FAN MOTOR TROUBLESHOOTING
Refer to Figure 56 for a basic fan motor troubleshoot- ing chart.
■TOOLS NEEDED — The following list includes rec- ommended tools and devices for working on the fan motor of 52C,P units.
Gloves
Safety Glasses
Regular and Phillips Head Screw Drivers
Small Adjustable Wrench
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 qualified service personnel should perform installation and service procedures on these units. Untrained personnel may perform basic mainte- nance tasks such as cleaning and replacing filters. Refer to UNIT DISASSEMBLY section of this man- ual for proper procedures to disconnect power to 52C,P units.
The Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
FIGURE 55 — TWO-SPEED, PERMANENT
SPLIT CAPACITOR MOTOR (PSC)
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 floor 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 52C,P unit may weigh up to 150 pounds. Use a lifting 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 first test requires checking the electrical resis- tance between 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.Open the control box as detailed in the UNIT DISASSEMBLY section.
3.Label and disconnect the fan motor wires from the selector switch and capacitor as shown in Figure 54.
4.Measure and record the resistance between the black wire and each of the other wires. Make sure the motor is cool before attempting to measure resistance. The internal thermostat of the motor may be electrically open and will not close until the motor cools. See Figure 57 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, find 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 infi- nite. Make sure the motor is cool before attempt- ing to measure resistance. The internal thermostat of the motor may be electrically open and will not close until the motor cools. A motor that has measurable resistance to ground is shorted to ground and must be replaced.
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