R31818 – FAN BLADE (3, 18″, 33°, CCW, HUBLESS)

Replacement condenser fan blade for HVAC outdoor units. If the original blade is cracked, bent, or missing pieces, replacing it restores proper airflow across the condenser coil — which is critical for cooling performance. Match the diameter, blade count, pitch, and rotation direction to your original blade.

Specs: 18″ diameter, 3 blades, 33° pitch, counterclockwise (CCW), hubless (no hub), aluminum construction

Replaces: N/A

Fits: Most residential and commercial HVAC condenser units requiring a 18-inch CCW blade

Need help? See our AC Fan Not Spinning Guide.

In stock at Open To Public HVAC Parts in Dallas. We test parts at the counter before you buy. Call or text (214) 340-9421.

Specs

• TypeCondenser fan blade
• Blade Count3 blades
• Diameter18"
• Pitch33°
• RotationCCW (counter-clockwise from shaft end)
• Hub StyleHubless (motor shaft direct)
• Shaft Diameter1/2" typical (verify)
• OEM CompatibilityUniversal

Cross-reference numbers

This part replaces the following OEM and aftermarket numbers:

• R31818

Not sure if your number matches? Call (214) 340-9421 or bring the old part in — bench-testing is free.

Fits these models

• Universal aftermarket condenser fan blade — fits residential AC and heat pump condensers with matching diameter / pitch / rotation / hub style
• Common applications: Rheem RA13/RA14/RA16, Goodman GSX13/14/16, Trane XR13/14/16, Carrier / Bryant 13-16 SEER, York / Coleman, Lennox 13-16 SEER
• Verify ALL 5 specs match your existing blade: diameter (16-28"), pitch angle (18-34°), blade count (2/3/4), rotation (CW or CCW), and hub style (hubless vs hub-on-intake)

How do I tell CW vs CCW rotation -- and does it matter for my motor?

Look at the front of the blade. Watch which way it turns when the system is running. CW = clockwise as you face the blade; CCW = counter-clockwise. The arrow stamp on the blade hub also marks rotation. If your motor is reversible (most modern condenser fan motors are), you can use either CW or CCW blade and just wire the motor to match. Non-reversible motors require matching the blade to the motor's fixed direction. Check the motor's data plate or terminal cover for a wiring diagram showing reversible operation.

Can I go up in diameter or pitch?

Pitch is forgiving -- within about 3 degrees is fine. A 27-degree blade will work in place of a 25 or 30 degree blade. Diameter is NOT forgiving -- bigger diameter risks hitting the condenser cabinet; smaller diameter creates an air gap that kills capacity. Match diameter exactly. Going up significantly in pitch (more than 3 degrees) increases CFM and amp draw -- verify your motor's amp rating before installing.

How do I install a fan blade?

1. Slide the blade onto the motor shaft, aligning the hub set-screw with the FLAT spot on the shaft. 2. Position the blade so the leading edge is 1/2"-3/4" inside the venturi (the round opening in the condenser top). 3. Tighten the set-screw on the flat spot. Apply blue thread-locker if available. 4. Spin by hand -- should turn freely with no wobble. 5. Power up briefly to verify rotation direction matches the arrow.

What's a hubless blade?

A hubless blade has the motor shaft pass through a center mounting hole with set-screws directly on the blade hub. A hubbed blade has a separate metal hub that bolts to the blade and holds the set-screws. Hubless = simpler, fewer parts; hubbed = stronger, more common on heavier-duty applications.

Why is my new blade vibrating?

Out-of-balance blade or bent hub. Stop the system immediately -- vibration will destroy the motor bearings. Check for: bent blade tip (impact damage), missing balance clip, loose hub, or wrong blade for the motor. Bring it back; we'll match a balanced replacement.