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Z-Flex Vent 3" or 4" Termination Hood with Backflow Preventer Damper

by Z-Flex
Original price $138.50 - Original price $142.46
Original price
$138.50 - $142.46
Current price $138.50


Vent Termination Hood with backflow preventer (damper). Single not double wall pipe, but will work properly with double wall pipe. Essential for tankless water heater venting, as it prevents freezing air from entering into the venting system and freezing the heater's pipes, damaging the heater and voiding the warranty.

Z-Vent does not manufacture a 5" vent termination hood with damper...only 3" and 4".

Flange dimensions for the 4" diameter hood: 7.25" x 7.25".

Made in AmericaFeatures:

• Simple gasketed connection requires no sealant
• Offers the highest pressure rating available
• Can be cut to desired length on site
• Smooth finish and perfect fit with new fusion-welded pipe seams
• Compatible with all single-wall Z-Flex Z-Vents
• Vent material: AL29-4C stainless steel
• Certification: Tested to meet or exceed Underwriters Laboratories (UL) spec UL1738 and ULS636
• Approval: Cat II, III, IV venting
• Limited Lifetime Warranty

Compatibility and cross reference:

The 4" diameter version of this item is compatible with the following tankless water heaters, as shown in their manual:

American Water Heaters GT-510-P/N Indoor Liquid Propane/Natural Gas
American Water Heaters GT-310-P/N Indoor Liquid Propane/Natural Gas
American Water Heaters GT110-P/N Indoor Liquid Propane/Natural Gas
A. O. Smith ATI-510-N/P Indoor Propane/Natural Gas
A. O. Smith ATI-310-N/P Indoor Propane/Natural Gas
A. O. Smith ATI-110-N/P Indoor Propane/Natural Gas
GSW GSWT-110/310
GSW GSWT-520/540
Marey 5L*
Marey 10L*
Reliance Water Heaters TS-510-GI
Reliance Water Heaters TS-310-GI
Reliance Water Heaters TS-110-GI
State Industries 510 Series
State Industries 310 Series
State Industries 110 Series
Takagi T-T-KJr2 Indoor/Outdoor Propane/NG
Takagi T-K4 Indoor/Outdoor Propane/NG

* Since these heaters are natural rise systems, they can only utilize a backflow preventer (damper) if they also include a low CFM booster fan and a thermostat to regulate when the fan should turn on.


Z-Vent SVE Series IV Installation and Maintenance Instructions, 3" to 24", Single & Double Wall

Z-Vent Dimensional Specifications