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: Service Manual

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A220822

Fig. 19 – Outdoor Fan Adjustment

The bearings are permanently lubricated, therefore, no oil ports are

provided.
For suspected electrical failures, check for loose or faulty electrical

connections, or defective fan motor capacitor. Fan motor is equipped

with thermal overload device in motor windings which may open under

adverse operating conditions. Allow time for motor to cool so device can

reset. Further checking of motor can be done with an ohmmeter. Set

scale on R X 1 position, and check for continuity between 3 leads.

Replace motors that show an open circuit in any of the windings. Place 1

lead of ohmmeter on each motor lead. At same time, place other

ohmmeter lead on motor case (ground). Replace any motor that shows

resistance to ground, arcing, burning, or overheating.

Compressor Plug

The compressor electrical plug provides a quick-tight connection to

compressor terminals. The plug completely covers the compressor

terminals and the mating female terminals are completely encapsulated

in plug. Therefore, terminals are isolated from any moisture so corrosion

and resultant pitted or discolored terminals are reduced. The plug is

oriented to relief slot in terminal box so cover cannot be secured if wires

are not positioned in slot, assuring correct electrical connection at the

compressor. The plug can be removed by simultaneously pulling while

“rocking“ plug. However, these plugs can be used only on specific

compressors. The configuration around the fusite terminals is outlined

on the terminal covers. The slot through which wires of plug are routed

is oriented on the bottom and slightly to the left. The correct plug can be

connected easily to compressor terminals and plug wires can easily be

routed through slot terminal cover.
It is strongly recommended to replace the compressor plug should a

compressor fail due to a suspected electrical failure. At a minimum,

inspect plug for proper connection and good condition on any

compressor replacement.

Low-Voltage Terminals

The low-voltage terminal designations, and their description and

function, are used on all Small Packaged Products (SPP) condensers.
W—Energizes first-stage supplemental heat.
R—Energizes 24-v power from transformer.
Y—Energizes contactor for first-stage cooling or first-stage heating for

heat pumps.
O—Energizes reversing valve on heat pumps.
C—Common side of transformer.
G—Indoor Fan

Ground Circuit

To determine if a wire has broken or come in direct contact with shell,

causing a direct short to ground, follow these steps:

1. Recover all refrigerant charge.
2. Using an ohmmeter on R X 10,000 ohm scale or megohmmeter

(follow manufacturer’s instructions).

3. Be sure all power is off.
4. Discharge all capacitors.
5. Remove compressor plug.
6. Place one meter probe on ground or on compressor shell. Make a

good metal-to-metal contact. Place other probe on terminals C, S,

and R in sequence.

7. Note meter scale.
8. If reading of 0 or low resistance is obtained, motor is grounded.

Replace compressor.

Compressor resistance to ground should not be less than 1000 ohms per

volt of operating voltage.
Example:
230 volts X 1000 ohms/volt = 230,000 ohms minimum.

Short Circuit

To determine if any wires within windings have broken through their

insulation and made contact with other wires, thereby shorting all or part

of the winding(s), be sure the following conditions are met.

1. Correct motor winding resistances must be known before testing,

either from previous readings or from manufacturer’s

specifications.

2. Temperature of windings must be as specified, usually about 70ºF

(21ºC).

3. Resistance measuring instrument must have an accuracy within ±

5-10 percent. This requires an accurate ohmmeter such as a

Wheatstone bridge or null balance-type instrument.

4. Motor must be dry or free from direct contact with liquid

refrigerant.

Make This Critical Test
(Not advisable unless above conditions are met)

1. Be sure all power is off.
2. Recover all refrigerant charge.
3. Discharge all capacitors.
4. Remove wires from terminals C, S, and R.
5. Place instrument probes together and determine probe and lead wire

resistance.

6. Check resistance readings from C-R, C-S, and R-S.
7. Subtract instrument probe and lead resistance from each reading.

If any reading is within ±20 percent of known resistance, motor is

probably normal. Usually a considerable difference in reading is noted if

a turn-to-turn short is present.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Turn off all power before servicing or replacing fan motor. Be sure unit

main power switch is turned off. Lock out and tag with suitable warning

label.

FAN
HUB