service manual for 6700, 7000, 8000 & 9000 series air conditioners

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condition can be analyzed by using an ohm meter. Be sure toremove all the leads from the compressor terminals beforemaking this check.1) If the resistance between any two terminals is 0ohms, the motor windings are shorted.2) If the resistance between any terminal and thecompressor housing is anything but infinity, thewinding is grounded.3) If the resistance between any two terminals isinfinity, the winding is open.On a good compressor, the highest resistance will be betweenthe R (run) and S (start) terminals. The lowest resistance willbe between the C (common) and R (run) terminals. Theintermediate resistance will be between the C (common) andS (start) terminals. Notice that compressors have theidentification of the terminals marked on either the terminalcover or on the compressor housing.7. Overload Switchthrough the condenser coil.* Some models use a squirrel cage on both ends of the motor.An important step in installing a replacement fan motor is tocheck the direction of rotation before it is installed. On allmodels, the condenser fan pulls the air through the coil.Fan Motor Check ProcedureIf a fan motor refuses to perform properly, it can be checkedin the following manner:9. Be sure the motor leads are connected to the properpoints –a) The black wire from the motor connects to ablack wire inside a wire nut then the blackwire connects through the disconnect plugto the selector switch. The red wire fromthe motor connects to a red wire in a wirenut then the red wire connects through thedisconnect plug to the selector switch.Mounted on the outside of the compressor housing is a twoterminal overload switch. Note: We have a few models withinternal overloads that are non-serviceable. The switch isconnected in series with the common terminal, so if theswitch opens, it will cut the power to the compressor motor.The switch will open as the result of either or both of twoconditions that could be harmful to the compressor.1) High Amperes (Current)The switch contains a heater which increases in temperatureas the current increases. The higher temperature warps theswitch and will cause it to open before the windings reach adangerous temperature.2) High Temperature (Thermal)The switch is clamped tightly against the compressor housingand located close to the windings. Therefore, as the windingsreach a higher temperature, it takes less current to cause theswitch to open.As can be seen, the switch is always affected by acombination of current to the compressor and windingtemperature.8. Fan MotorThe air conditioning unit has one double end shaft fan motor.On one shaft end is mounted a centrifugal or squirrel cageblower which draws air (return air) out of the recreationalvehicle and blows the conditioned air down into therecreational vehicle. On the other end is mounted an axialflow or propellor type fan which circulates outdoor airb) The white wire from the motor connects tothe fan capacitor or a white wire in a wirenut then the white wire connects throughthe disconnect plug to the thermostat.c) The brown wires from the motor connect tothe fan capacitor.2. To check the motor winding resistance carefully,check the resistance between each of the wires andground (preferably a copper refrigerant tube for agood connection). These readings must be infinity.Any continuity means the windings are grounded.If there is a reading of 0 between any two leads, themotor is shorted and is no good. If there is a readingof infinity (no meter reading at all) between any twoleads, the winding is open and the motor is no good.Note:A motor with 2 brown leads will have anO reading between 1 brown wire and eitherthe black or white wire.8
9. Run CapacitorsThe purpose of the run capacitors is to give the motorsstarting torque and to maintain high power factor duringrunning. The run capacitors are always connected betweenthe start and run or main terminals of the motor.On some older models, one of the terminals of the runcapacitors will have a red dot (the identified terminal). Theidentified terminal should always be connected to the run ormain terminal of the motor and to the neutral line.CAPACITORSGood CapacitorIf the capacitor is good, the indicator will move from infinity(the left side), towards zero ohms and slowly return back toinfinity. Reverse the leads and test again. The result shouldbe the same.OHM METERCAPACITORCapacitor CheckThere are several capacitor test devices available. The ohmmeter is one of them. The ohm meter cannot verify acapacitors MFD (microfarrad) value. However, the followingprocedures will show you how to use an ohm meter todetermine if the capacitor is good, open, shorted or grounded.Before testing any capacitor, always perform the followingprocedure:* This test must be done with a analog type meter.a) Disconnect all electrical power to the air conditioner.b) Discharge the capacitor with a 20,000 ohm (approx.3 watt) resistor or larger.c) You may discharge capacitors with a standard voltmeter if you use a scale over 500 volts and touch theleads (one lead to each side of the capacitor). Thevolt meter will discharge the capacitor.HIGHOpen CapacitorOKLOWIndicator sweeps back and forthas shown above. Capacitor is good.If the capacitor is open, the indicator will show no deflectionor movement. Reverse the leads and test again. If there is noindicator movement on the second test, the capacitor is open.Open capacitors are defective and must be replaced.OPENHIGH LOWd) Identify and disconnect the wiring from thecapacitor.e) Set and zero the ohm meter on the “highest” scale.When testing for a good, open or shorted capacitor,perform the following checks: Place the ohm meterleads across the capacitor terminals (one lead oneach terminal) and perform a continuity test. Thenobserve the action of the meter needle or indicator.Reverse the leads and test again. The result shouldbe the same. Note: If the capacitor had not beenproperly discharged, a false reading could beindicated on the first test. Always test several times(reversing the leads with each test). This will verifythe capacitors condition.Shorted CapacitorIndicator shows no movement.Needle stays to the left side. If needleshows no movement after reversing theleads, the capacitor is open.If the capacitor is shorted, the indicator will move towards and sometimes hit zeroohms, and will stay there. This indicates a completed circuit through the inside ofthe capacitor (shorted). Shorted capacitors are defective and must be replaced.SHORTHIGH LOWIndicator moves to the right sideof the scale and stays there(indicating a completed circuit).The capacitor is shorted.9
Page 3 and 4: TABLE OF CONTENTSBasic Components a
Page 6: 5. Suction LineThe suction line is
Page 11 and 12: 1. Ammeter And Its UseAn ammeter is
Page 13 and 14: 1. Most all electronic leak detecto
Page 17 and 18: The customer turns the system to fa
Page 19 and 20: 6. “Plugged up cap tube.”A cap
Page 21 and 22: 6798-7XX, 6798A7XX SERIES6799-7XX,
Page 23 and 24: CEILING ASSEMBLY WIRING DIAGRAMS675
Page 25 and 26: WIRING DIAGRAM9330X713, 9330X714 CO

service manual for 6700, 7000, 8000 & 9000 series air conditioners

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