What HP motor do I need for my Lennox unit?

The correct replacement for Lennox model OEM Lennox Condenser Fan Motor — 78F90 is this exact part. It is the factory-specified replacement with exact OEM specifications. Using a part with different specifications can cause equipment damage or void your warranty. You can verify this by checking the data plate on your Lennox equipment which lists the model number OEM Lennox Condenser Fan Motor — 78F90.

My AC fan is not spinning. What part do I need?

A fan that does not spin, spins slowly, or makes grinding or squealing noises needs a new motor. Grinding means the bearings have failed. Squealing means the bearings are dry. No spin with a humming sound means the capacitor may be the issue. Check the motor capacitor before replacing the entire motor.

Lennox

OEM Lennox Condenser Fan Motor — 78F90

Name: OEM Lennox Condenser Fan Motor — 78F90
Brand: Lennox
SKU: LNX-78F90
Price: 99.95 USD
Availability: InStock

SKU: LNX-78F90 Brand: Lennox

$99.95 $139.95

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The genuine OEM Lennox 78F90 fan motor turns the condenser fan blade in your outdoor unit, pulling air across the coil to release the heat absorbed from inside your home. Consistent, rated airflow is what allows the refrigerant to condense properly, so this motor is essential to your Lennox system's cooling capacity and efficiency. It is built for continuous outdoor duty against heat, weather, and vibration.

Common failure symptoms: the outdoor fan runs slowly or not at all, the unit overheats and trips on high-pressure lockout, warm air from the vents, loud humming or bearing noise, or a motor that's hot to the touch and shuts down after a few minutes. A failing fan motor frequently causes the compressor to overheat, so prompt replacement protects the rest of the system.

Why OEM matters: the 78F90 matches your Lennox unit's exact horsepower, RPM, rotation direction, and shaft dimensions. Generic motors risk incorrect airflow, poor heat rejection, and premature compressor wear. Installing the factory-specified OEM motor guarantees rated cooling performance, proper capacitor pairing, and a precise, trouble-free fit.

Shipping Information

Orders placed before 3PM CST ship same business day
Standard delivery: 2-5 business days
Express shipping available at checkout
Free shipping on orders over $75
Tracking number emailed upon shipment

Return Policy

30-day returns on unused parts in original packaging
Electrical parts (capacitors, contactors, control boards) are final sale once installed
Email info@nationalhvacparts.com to initiate a return
Refunds processed within 5-7 business days

OEM Lennox Condenser Fan Motor —...

$99.95

Frequently Asked Questions

Does this Fan Motor fit my Lennox OEM Lennox Condenser Fan Motor — 78F90?

Yes. This is the factory-specified OEM fan motor for the Lennox OEM Lennox Condenser Fan Motor — 78F90. It is a direct drop-in replacement that fits without modification. Always verify the model number on your equipment nameplate before ordering.

How do I replace the fan motor on my Lennox OEM Lennox Condenser Fan Motor — 78F90?

Difficulty: Medium-Hard (1–2 hrs)
Step 1: Turn off breaker. Step 2: Note motor specs: HP, RPM, voltage, rotation direction. Step 3: Remove old motor from mounting. Step 4: Transfer fan blade to new motor. Step 5: Mount new motor, reconnect wiring. Step 6: Restore power, verify rotation direction.

My AC fan isn’t spinning. What part do I need?

Fan not spinning, spinning slowly, or making grinding/squealing noises = motor failure. Grinding = bearings failed. Squealing = bearings dry. No spin + hum = check the motor capacitor first before replacing the entire motor.

Is this fan motor compatible with Bryant or Payne too?

Many Lennox parts are cross-compatible with Bryant and Payne since all three brands are manufactured by Carrier Global Corporation. The same physical part is often used across brand labels with different model numbers. To verify: check your Bryant or Payne equipment service manual for cross-compatible part numbers, or email info@nationalhvacparts.com with your model number.

Should I use OEM or aftermarket for my Lennox fan motor?

OEM recommended for reliability and warranty compatibility. OEM parts match exact factory specifications for proper fit, performance, and safety. While aftermarket alternatives cost less upfront, the risk of improper fit and reduced lifespan usually makes OEM the better value long-term.

How fast does National HVAC Parts ship?

Orders placed before 3:00 PM CST ship the same business day. Standard delivery is 2–5 business days anywhere in the continental United States. Express shipping available at checkout. We ship from Houston, TX to all 50 states. 30-day return policy on all parts.

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OEM Lennox Condenser Fan Motor — 78F90

Shipping Information

Return Policy

Frequently Asked Questions