Metal-Fab MFG# 3M1x4 Vent Pipe Increaser 3″ to 4″ B-Vent Adapter HVAC LP Gas

Metal-Fab 3M1x4 B-Vent Pipe Increaser – 3″ to 4″ Adapter | MFG# 3M1x4Upgrade your venting system with the Metal-Fab 3M1x4 increaser, engineered to transition from a 3-inch to a 4-inch B-vent pipe connection. Designed for Category I gas appliances such as LP gas water heaters, propane furnaces, and natural gas boilers, this vent adapter ensures a safe and efficient increase in flue size to meet code or design specs.Product Features:Increases vent size from 3″ to 4″Precision snap-lock fit for secure connectionGalvanized steel construction resists rust and high temperaturesCompatible with Metal-Fab double-wall B-Vent systemsListed for propane, LP, and natural gas venting applicationsMeets UL 441 standardsTypical Applications:Connecting vent stacks for upgraded equipmentRetrofits or code-required diameter increasesResidential and commercial LP/Natural Gas heating systemsThis adapter provides a safe gas venting solution when increasing flue diameter and supports efficient exhaust ventilation.

Important Notice – Propane Parts, Accessories, and Regulators

This product, including but not limited to propane parts, accessories, fittings, hoses, valves, and regulators, must be installed and serviced by a licensed professional in accordance with all applicable local, state, and federal codes, regulations, and standards.

The seller assumes no responsibility for the installation, inspection, application, maintenance, or use of this product.

It is the sole responsibility of the buyer to ensure the product is appropriate for their intended application and that it is installed correctly by a qualified individual.

Improper installation, maintenance, or use of propane products may result in serious injury, death, fire, explosion, or property damage.

The buyer accepts all risks, liabilities, and potential consequences associated with the use of this product.

By purchasing this item, the buyer acknowledges that they have read, understood, and agreed to these terms and confirm that installation and use will be conducted by a properly licensed and qualified professional.