Before cleaning, servicing, performing maintenance or removing the chassis from the wall sleeve, disconnect 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 maintenance tasks such as cleaning and replacing filters. 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, specifications 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 floor around the work area should be clean and free of debris.
Make sure tools are the correct tools for job, and that they are working properly and in good condition.
The 52S unit may weigh up to 150 pounds. Use a lifting device or ask for assistance if the unit must be moved.
The following list includes recommended 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)
3/8-IN. SOCKET SET
CHANNEL LOCK PLIERS
VOLT-OHMMETER
5/16-IN. AND 1/4-IN. NUT DRIVERS
Before cleaning, servicing, performing maintenance or removing the chassis from the wall sleeve, disconnect 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 maintenance tasks such as cleaning and replacing filters. 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, specifications 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 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 52S unit may weigh up to 150 pounds. Use a lifting device or ask for assistance if the unit must be moved.
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 resistance 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. Remove the unit from the sleeve and open the control box as detailed in the GENERAL DISASSEMBLY section.
3. Label and disconnect the fan motor wires from the push button switch and capacitor as shown in Figure 5. Two-speed motors have 2 wires on the capacitor and 2 wires on the push button switch. Three-speed motors have 2 wires on the capacitor and 3 wires on the push button switch. Refer to the unit wiring diagram inside the control box.
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 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, find a motor of similar horsepower and voltage on the chart and compare it to the resistance measurements of your motor.
