Lennox CBX27UH Lennox Variable Speed Air Handler NO LIGHT Error Fix: No Power

Error code NO LIGHT on the Lennox CBX27UH Lennox Variable Speed Air Handler means: No Power. The control board has no power. Check circuit breaker, unit disconnect switch, and air handler fuse link or control circuit fuse.

The most successful fix is "Test and Replace Air Handler Fuse Link or Control Circuit Fuse" (medium difficulty, ~45 minutes). Estimated DIY cost: $10-$20. HomeMD has 2 community-ranked fixes for this error.

This error is rated critical severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Test and Replace Air Handler Fuse Link or Control Circuit Fuse") is rated medium difficulty and takes about 45 minutes. Tools needed: T20 Torx screwdriver, Multimeter.

DIY cost: $10-$20. Professional repair typically costs $120-$180. Many homeowners save money by trying the top-ranked community fix first.

The Lennox CBX27UH Lennox Variable Speed Air Handler has 8 other known error codes, including: AH BLOWER MOTOR FAIL (Blower Motor Failure), DRAIN PAN OVERFLOW (Condensate Drain Pan Overflow), EVAPORATOR COIL DIRTY (Indoor Coil Dirty / Restricted), FLASHING GREEN (Normal — Blower Running), FLASHING YELLOW (High Limit — Electric Heat), and 3 more.

Error code NO LIGHT also appears on 9 other Lennox models: EL296V Elite Series 96% AFUE Two-Stage Variable Speed Gas Furnace, ML14XC1 Merit Series 14 SEER Single-Stage Air Conditioner, ML196E Merit Series 96% AFUE Single-Stage Gas Furnace, SL280V Dave Lennox Signature Collection 80% AFUE Variable Speed Gas Furnace, SL297NV Dave Lennox Signature Collection 97% AFUE Modulating Variable Speed Gas Furnace, XC21 Dave Lennox Signature Collection 21 SEER Variable-Capacity Air Conditioner, and 3 more. The fix may vary by model, so check each model's specific page for tailored repair steps.