Fleetwood Discovery – AC Capacitor & Fan Motor Service

Fleetwood Discovery – AC Capacitor & Fan Motor Service

by

Complete repair guide for the Fleetwood Discovery – AC Capacitor & Fan Motor Service. Follow these steps to diagnose and fix the issue yourself.

Parts & Tools You’ll Need

Step 1: Diagnose AC Issues and Prepare Workspace

Start by running your AC unit for 10-15 minutes and listen for unusual grinding or squealing sounds, which indicate fan motor or capacitor failure. Turn off power at the main breaker and allow the system to cool for at least 30 minutes before touching any components. Gather all your tools and parts on the roof, and use a non-contact infrared thermometer to record the current air temperature differential between the return and supply ducts for baseline comparison after service.

Step 2: Remove Rooftop AC Shroud and Access Components

Unbolt the rooftop AC shroud using a socket wrench, typically 3/8-inch bolts around the perimeter—most Fleetwood Discovery units have 8-12 fasteners. Carefully lift the shroud straight up to avoid damaging the condenser fins, and set it aside on a clean towel. Take a photo of the capacitor and motor connections before disconnection so you can reference wire placement during reassembly.

Step 3: Test and Replace the Dual Run Capacitor

Use a multimeter set to the capacitance setting (μF scale) to test the existing capacitor; a reading below the rated microfarads (typically 35-55 μF for Dometic or Coleman-Mach units) confirms failure. Disconnect the capacitor leads from the fan motor and contactor terminals—take a photo or label each wire with masking tape. Install the replacement RV AC dual run capacitor by reconnecting wires to the exact same terminals, ensuring connections are tight and secure.

Step 4: Clean and Inspect the Fan Motor Assembly

Spray the fan motor housing and surrounding coils with AC evaporator/condenser coil cleaner foam, allowing it to sit for 5 minutes before rinsing with a soft brush and distilled water. Inspect the motor shaft for corrosion or wobbling by manually rotating the fan blades—they should spin freely without grinding sounds or excessive resistance. Check that the motor mounting bolts are tight and that the fan blade is centered; any imbalance will cause vibration and premature failure.

Step 5: Replace Fan Motor If Necessary and Straighten Fins

If the motor shaft is visibly corroded or the windings show burning marks, unbolt the 4-6 fasteners securing the motor housing and disconnect the fan motor from the capacitor terminals. Install the replacement RV rooftop AC fan motor by reversing the removal process, ensuring all bolts are torqued to 15-18 foot-pounds. Use the fin comb/coil straightener tool to gently realign any bent aluminum fins on the condenser coil by working in the direction of the fin rows.

Step 6: Reseal and Reinstall the AC Shroud

Apply a continuous bead of RV AC roof gasket and self-leveling sealant around all four sides of the shroud mounting surface, approximately 1/4-inch thick. Carefully lower the shroud back onto the unit and reinstall all bolts in a cross-pattern (diagonal) to ensure even seating and pressure distribution. Tighten bolts to 12-15 foot-pounds and allow sealant to cure for 24 hours before operating the AC unit.

Step 7: Run Full System Test and Verify Performance

Restore power at the main breaker and set the RV AC thermostat to cool mode at 72°F, running the unit for 20-30 minutes while monitoring operation. Use the non-contact infrared thermometer to measure supply and return duct temperatures—you should see a 15-20°F temperature differential; anything less may indicate a secondary issue. Listen for quiet operation without grinding, squealing, or rattling, and confirm that the roof gasket is holding and no water is pooling around the AC unit.