Complete repair guide for the KZ Durango – AC Capacitor & Fan Motor Service. Follow these steps to diagnose and fix the issue yourself.
Parts & Tools You’ll Need
- RV AC dual run capacitor (Dometic/Coleman-Mach)
- Rooftop AC fan motor
- RV AC thermostat / control board
- AC evaporator/condenser coil cleaner foam
- Rooftop AC shroud / outer cover
- AC roof gasket & self-leveling lap sealant
- Fin comb / coil straightener tool
- Non-contact infrared thermometer
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Step-by-Step Repair Guide
Step 1: Diagnose AC Issues and Safety
Start by identifying whether your KZ Durango’s AC is blowing warm air, making unusual noises, or failing to cool effectively—these symptoms often indicate capacitor or fan motor failure. Before beginning any work, disconnect your RV from all power sources and turn off the main breaker to prevent electrical shock and equipment damage.
Step 2: Remove Rooftop AC Shroud Carefully
Climb onto your RV roof with proper safety equipment and locate the bolts securing the outer AC shroud cover. Use a socket wrench to remove all fasteners, then gently lift away the shroud to expose the internal capacitor, fan motor, and coil components.
Step 3: Discharge and Replace Dual Run Capacitor
Using an insulated screwdriver, carefully discharge any remaining electrical charge in the old capacitor by touching the blade across both terminals. Disconnect the wire terminals from the failing capacitor, note their positions, and install the new dual run capacitor by reversing the removal process while matching wire colors and terminal positions.
Step 4: Clean Coils with Specialized Foam
Apply the AC evaporator and condenser coil cleaner foam liberally across all coil surfaces, allowing it to sit for the manufacturer’s recommended time to break down dirt and debris buildup. Use a soft brush or fin comb to gently remove loosened contaminants, being careful not to bend the delicate aluminum fins.
Step 5: Inspect and Replace Fan Motor
Examine the fan motor for visible damage, corrosion, or burnt wiring, and verify it rotates freely by hand before deciding on replacement. If replacement is necessary, disconnect the motor wiring harness and remove the mounting bolts, then install the new motor and reconnect all terminals securely.
Step 6: Reseal and Reinstall Shroud Cover
Apply a bead of self-leveling lap sealant around the gasket mounting surface to create a watertight seal before reinstalling the rooftop AC shroud. Align all bolt holes carefully and torque the fasteners evenly to prevent warping, then allow the sealant to cure per manufacturer specifications before exposing to water.
Step 7: Test AC Function and Temperature Output
Reconnect power to your RV and turn on the AC system, allowing it to run for several minutes while listening for normal fan operation and checking for leaks. Use your non-contact infrared thermometer to measure the temperature of the air exiting the vents—you should see a significant difference from the ambient temperature, confirming proper cooling operation.
Recommended Parts
| Part | Link |
|---|---|
| RV AC dual run capacitor (Dometic/Coleman-Mach) | View on Amazon |
| Rooftop AC fan motor | View on Amazon |
| RV AC thermostat / control board | View on Amazon |
| AC evaporator/condenser coil cleaner foam | View on Amazon |
| Rooftop AC shroud / outer cover | View on Amazon |
| AC roof gasket & self-leveling lap sealant | View on Amazon |
| Fin comb / coil straightener tool | View on Amazon |
| Non-contact infrared thermometer | View on Amazon |