1. Because of the spinning motion of the rotary, the mounts are critical. If vibration is present, check the
mounts carefully.
2. The electrical terminals on the rotary are in a different order than the reciprocating compressors. The terminal
markings are on the cover gasket. Use your wiring diagram to insure correct connections.
9.2.6 Refrigerant charge
1. The refrigerant charge is extremely critical. It must be measured charge carefully - as exact as possible to the
nameplate charge.
2. The correct method for charging the rotary is to introduce liquid refrigerant into the high side of the system
with the unit off. Then start compressor and enter the balance of the charge, gas only, into the low side.
The introduction of liquid into the low side, without the use of a capillary tube, will cause damage to the
discharge valve of the rotary compressor.
NOTE: All inoperative compressors returned for repair must have all lines properly plugged
with the plugs from the
replacement compressor.
9.3 Fan motor
A single phase permanent split capacitor motor is used to drive the evaporator blower and condenser fan.
A self-resetting overload is located inside the motor to protect against high temperature and high
amperage conditions.
9.3.1 Fan motor test
1. Determine that capacitor is serviceable.
2. Disconnect fan motor wires from fan speed switch or system switch.
3. Apply "live" test cord probes on black wire and common terminal of capacitor. Motor should run at high
speed.
4. Apply "live" test cord probes on red wire and common terminal of capacitor. Motor should run at low speed.
5. Apply "live" test cord probes on each of the remaining wires from the speed switch or system
switch to test
intermediate speeds.
9.4 Capacitor
A run capacitor is wired across the auxiliary and main winding of a single phase permanent split capacitor motor
such as the compressor and fan motor. A single capacitor can be used for each motor or a dual rated capacitor
can be used for both.
The capacitor's primary function is to reduce the line current while greatly improving the torque characteristics of
a motor. The capacitor also reduces the line current to the motor by
improving the
power factor of the load. Run
capacitor hook-up line side of the capacitor is marked with a red
dot and is wired to the line side of the circuit.
9.4.1 Capacitor test
1. Remove capacitor from unit.
2. Check for visual damage such as bulges, cracks, or leaks.
3. For dual rated, apply an ohmmeter lead to common (C) terminal and the other probe to the compressor (HERM)
terminal. A satisfactory capacitor will cause a deflection on the pointer, and then gradually move back to infinity.
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