Lennox CK40CT-18/24A-71 14.5" Width 24,000 BTU Coil

The Lennox CK40CT-18/24A-71 is a cased upflow evaporator coil for 1.5 to 2 ton R-454B systems, with a factory-installed R-454B expansion valve. It fits a 14.5-inch A cabinet Lennox furnace.

Key specs

• Capacity: 1.5 to 2 tons nominal
• Refrigerant: R-454B only, with a refrigerant detection sensor installed at the factory
• Cabinet: A size, 14.5 inches wide
• Connections: 3/4-inch suction and 3/8-inch liquid, sweat, plus two 3/4-inch FPT condensate drains on an anti-microbial drain pan
• Construction: Lennox Quantum coil with aluminum tubing and ripple-edged aluminum fins

Reading the model number

The first C means indoor coil, K means R-454B, and 40 is the Quantum coil series. The C after 40 is the upflow cased cabinet, T is the factory expansion valve, 18/24 is the 1.5 to 2 ton size, A is the 14.5-inch cabinet that matches A furnaces, and 71 means R-454B only. You may also see it written as CK40CT-18-24A-71.

What it pairs with

It lines up with Lennox furnaces that carry the A cabinet letter. The AHRI Directory lists it with these Lennox units we sell: EL15KC1, EL16KC1, EL18KCV, EL22KCV, ML13KC1, ML14KC1, and ML17KC2 air conditioners. The best listed match we carry is the EL18KCV-024-230 air conditioner on an ML180UH045XE36A furnace, at 17 SEER2.

Sizing and fit

Choose the size to match your outdoor unit's tonnage, and the cabinet letter to match your furnace. If your furnace has no built-in RDS mitigation control, it needs Lennox's RDS blower control board, ordered separately. Have your outdoor unit's model number ready when you call, and we'll check it against Lennox's AHRI matchups.

Warranty and registration

HVAC USA is an authorized Lennox reseller, and everything we sell is new factory equipment. Your full Lennox warranty applies when a licensed, manufacturer-certified contractor installs your system and registers it within 60 days.

Shipping and help

It ships from our Kansas City warehouse to the lower 48 states and D.C. It ships free when your cart also has an item that ships free, except to Washington, Oregon, and Idaho. For Alaska, Hawaii, Puerto Rico, other U.S. territories, or an APO or FPO address, call or text us for a quote. Call (913) 364-0070, Monday to Friday, 9am to 5pm CST, and we'll help you confirm sizing and an AHRI-matched pairing before you order.