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

Name: Metal-Fab MFG# 3M1x4 Vent Pipe Increaser 3" to 4" B-Vent Adapter HVAC LP Gas
SKU: 3MIx4
Price: 54.26 USD
Availability: InStock

SKU: 3MIx4

$54.26

In stock

Same-item volume pricing

Quantity	Unit price	Saving
1–4	$54.26	0%
5–9	$51.55	5%
10+	$48.83	10%

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Product Description

Overview

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.

Product details

Part / SKU	3MIx4

Package includes

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

Included components and any stated pack quantity are as described in this listing. Optional accessories shown separately are sold separately unless expressly included above.