InOvate LT90 Dryer-Ell – 90° Dryer Vent Elbow

Long-Turn Dryer Elbow with Reduced Airflow Restriction

The InOvate LT90 Dryer-Ell is a 4" long-turn 90° dryer exhaust elbow engineered to reduce friction loss and airflow restriction compared with conventional sectioned elbows. Its 10" radius and smooth interior allow the fitting to perform much more like straight duct, helping preserve allowable dryer exhaust run length.

Based on ASHRAE methodology, the LT90 has an equivalent duct length of approximately 1.5 feet, rather than the larger penalty typically associated with a standard 90° dryer elbow. The manufacturer also cites UL testing showing substantially less airflow impact than a typical sectioned elbow.

Learn how dryer transition duct and long-radius fittings can help reduce airflow restrictions in our Dryer Vent Hose Guide.

Buying for a multifamily or commercial project? Request contractor & quantity pricing.

Ideal for:

• Long dryer exhaust duct runs
• Projects approaching maximum allowable duct length
• Replacing restrictive short-radius 90° elbows
• Attic and floor-joist dryer exhaust routing
• Applications where a booster fan may otherwise be considered
• 10" long-turn radius
• Smooth interior
• 4" dryer duct diameter
• 18" overall length
• 26-gauge aluminized steel
• 1.5 ft equivalent length
• Made in the USA
• Potential alternative to booster fans in certain long-run applications

LT90 Dryer-Ell Specifications

• Model: LT90
• Duct Diameter: 4"
• Elbow Angle: 90°
• Radius: 10" long-turn radius
• Overall Length: 18"
• Equivalent Duct Length: Approximately 1.5 ft based on ASHRAE methodology
• Material: 26-gauge aluminized steel
• Interior: Smooth interior for reduced airflow restriction
• Application: Residential, multifamily and commercial dryer exhaust systems
• Made in the USA

Why Equivalent Length Matters

Every elbow in a dryer exhaust system adds resistance to airflow and effectively reduces the allowable length of the duct run. The LT90's long-turn design minimizes this penalty, making it particularly useful on longer or more complex dryer exhaust runs where maintaining airflow is important.

Installation Notes

The LT90 is supplied as a two-piece fitting and assembles using fastening tabs. An airflow arrow indicates the proper direction from the dryer and helps maintain the correct male-to-female duct connection.

When installing the LT90 with a Dryerbox 4D, InOvate specifies using a 3" section of snaplock pipe between the 4D port and LT90 to provide adequate transition for the flex connection. Always follow the manufacturer's installation instructions and applicable local code requirements.

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