Choosing the right venting parts is just as important as choosing the water heater itself. A properly matched kit helps support safe operation, efficient exhaust flow, and a cleaner installation.
Below, we focus on 10 tankless water heater exhaust vent kit options for common 2-inch and 3-inch setups, with attention to fit, materials, and compatibility.
Best 10 Tankless Water Heater Exhaust Vent Kit Picks for 2026
Best for Clean Horizontal Termination
DiversiTech HVENT2 2-Inch Vent Kit
- Low-profile look hides intake and exhaust piping
- Includes fittings for a smoother installation
- Supports horizontal and vertical venting setups
Best For: Homeowners and installers who want a tidy termination kit for compatible tankless water heaters or furnaces.
Best for 2-Inch Vents
SP20285 Horizontal Vent Termination Kit
- Fits 2-inch vent pipe setups
- Horizontal outside-wall termination design
- Includes screws for installation
Best For: Homeowners or installers needing a 2-inch horizontal vent termination kit for a high-efficiency tankless gas water heater.
Best for Easy Installation
3" Stainless Steel Direct Vent Kit
- Complete kit with pipe, elbow, tape, clamp, and wall flange
- 304 stainless steel for heat and corrosion resistance
- Standard 3-inch fittings simplify setup
Best For: DIYers who need a complete 3-inch vent kit for a gas tankless water heater.
Best for Easy DIY Install
FOGATTI Stainless Steel Vent Kit
- T304 stainless steel for corrosion resistance and heat tolerance
- Horizontal venting parts included for residential tankless heaters
- Simple assembly makes it a solid DIY-friendly option
Best For: DIY homeowners installing a compatible gas tankless water heater vent setup.
Best for Through-Wall Installs
Rheem RTG20280-1 Horizontal Vent Kit
- Stainless steel build for durability
- Includes wall plate, screws, and elbow
- Fits walls up to 10 inches thick
Best For: Compatible Rheem tankless gas units needing a horizontal through-wall vent termination.
Best Simple Pick
- T304 stainless steel resists corrosion and heat
- Modular pieces make sizing easier
- Includes hood, elbow, pipes, and wall thimble
Best For: GASLAND owners and buyers needing a simple 3-inch horizontal venting kit.
Best for Clean Horizontal Termination – DiversiTech HVENT2 2-Inch Vent Kit
If you want a tidy, code-conscious way to finish a vent run, this tankless water heater exhaust vent kit is built for high-efficiency fossil-fuel appliances and helps conceal both intake and exhaust piping. It’s a practical fit when you want a cleaner exterior look without piecing together extra outside fittings.
Best For: Homeowners and installers who need a compact, low-profile termination kit for tankless water heaters or high-efficiency furnaces.
Pros:
- Includes the fittings needed for a more complete installation
- Low-profile design helps hide intake and exhaust pipework
- Works with horizontal through-wall and vertical through-roof setups
- Sized for residential high-efficiency appliance applications
Cons:
- Only works with compatible 2-inch venting systems
- May be overkill if you only need a basic termination cap
For buyers prioritizing a neat exterior finish and fewer missing parts at install time, this tankless water heater exhaust vent kit is a strong, practical choice. It’s less about flashy extras and more about giving you a cleaner termination solution that’s ready for common residential venting needs.
Best for 3-Inch Venting – Stainless Steel 3-Inch Tankless Water Heater Vent Kit
If you need a tankless water heater exhaust vent kit for a 3-inch system, this stainless steel option is built for a straightforward replacement or new install. It includes the elbow and 24.1-inch vent section, making it a practical fit for compatible CAMPLUX, Ranein, FOGATTI, Forimo, ORBEK, MIZUDO, GASLAND, and Marey units.
Best For: Buyers who specifically need a 3-inch vent kit with an elbow for compatible gas tankless water heaters.
Pros:
- Made for 3-inch venting, with a clear size notice to reduce ordering mistakes
- Stainless steel construction helps resist corrosion and wear
- Includes a 3-inch elbow and 24.1-inch section for a more complete install
- Compact design can help with tighter residential or commercial setups
Cons:
- Only works with 3-inch systems, so it is not a universal fit
- Compatibility depends on the specific heater model and venting requirements
- No size flexibility if your setup uses 2-inch, 4-inch, or 5-inch piping
Overall, this tankless water heater exhaust vent kit makes sense when you already know you need a 3-inch stainless steel vent solution and want a simple, compatible kit with the elbow included.
Best for 2-Inch Vents – SP20285 Horizontal Vent Termination Kit
If you need a tankless water heater exhaust vent kit for a 2-inch setup, this SP20285 horizontal termination kit is aimed at straightforward exterior-wall venting on high-efficiency gas units. It’s the kind of accessory to consider when you want a matched termination solution rather than piecing together incompatible parts.
Best For: Homeowners or installers working with 2-inch tankless gas water heater venting who need a horizontal outside-wall termination kit.
Pros:
- Designed for 2-inch pipe compatibility
- Horizontal termination layout suits exterior-wall installs
- Includes screws for a more complete kit
- Good fit for high-efficiency tankless gas water heaters
Cons:
- Only works for systems that match the specified 2-inch vent size
- Not a universal solution for every tankless water heater exhaust vent kit application
For buyers planning a clean sidewall exhaust run, this kit is a practical, purpose-built option that keeps the install focused on the right pipe size and venting style. If your heater calls for a 2-inch horizontal termination, it’s a solid category match for a tankless water heater exhaust vent kit.
Best for Easy Installation – 3" Stainless Steel Direct Vent Kit
If you need a practical tankless water heater exhaust vent kit for a standard 3-inch setup, this stainless steel direct vent kit covers the core parts without forcing you to source extras. It’s built for straightforward vent runs, with a smooth inner wall to help exhaust flow efficiently and standard fittings that make installation more manageable.
Best For: DIYers and homeowners who want a complete 3-inch venting kit for a gas tankless water heater with basic installation hardware included.
Pros:
- Includes the main vent components plus tape, clamp, and wall flange
- 304 stainless steel construction adds heat and corrosion resistance
- Smooth inner wall supports efficient exhaust airflow
- Standard 3-inch fittings help simplify setup and extension
Cons:
- Only works for systems that require a 3-inch vent size
- May still require installer knowledge for proper code-compliant venting
Overall, this tankless water heater exhaust vent kit is a solid pick when you want a durable, ready-to-install option for a common 3-inch vent configuration. It stands out more for completeness and ease of setup than for advanced customization.
Best for Easy Setup – SP20285 Horizontal Vent Termination Kit
If you need a tankless water heater exhaust vent kit for a 2-inch PVC or ABS setup, the SP20285 horizontal vent termination kit is built for a straightforward outside-wall install. It includes the key parts needed for vent termination and is designed to keep intake and exhaust lines neatly finished while supporting safe, efficient venting for compatible high-efficiency appliances.
Best For: Homeowners who want a simple horizontal vent termination solution for compatible tankless gas water heaters and other high-efficiency appliances.
Pros:
- Includes screws and termination hardware for a cleaner, easier install
- Flush-mount design helps conceal intake and exhaust piping
- Works with 2-inch PVC and ABS piping on compatible systems
Cons:
- Only fits 2-inch piping, so compatibility must be checked first
- Sold as a vent termination kit, not the full vent pipe run
Overall, this tankless water heater exhaust vent kit is a practical pick if you already know your pipe size and want a tidy, no-fuss horizontal termination option. The main value is convenience and compatibility for the right setup rather than broad fitment across every system.
Best for Simple Direct-Vent Runs – Blulu Stainless Steel Vent Pipe Kit
If you need a straightforward tankless water heater exhaust vent kit for an indoor gas unit, this Blulu set covers the basic direct-vent pieces without overcomplicating the install. The 3-inch stainless steel components are designed for horizontal termination, with a crimped end that helps make ductwork connections easier.
Best For: DIYers and homeowners who want a basic stainless steel vent kit for a direct-vent tankless water heater setup.
Pros:
- Includes both a vent pipe and elbow for a simpler starter setup
- 201 stainless steel construction adds heat resistance and durability
- Horizontal termination design with crimped end supports easier installation
- Compact 19.7-inch pipe length fits many tight venting layouts
Cons:
- May not suit larger or nonstandard venting configurations
- Only covers the listed components, so some installs may need extra parts
- Fit depends on matching the exact 3-inch OD sizing
This tankless water heater exhaust vent kit is a practical pick if you want a basic, corrosion-resistant direct-vent solution for a small-to-midsize installation. It is best viewed as a focused hardware kit rather than a full all-in-one venting system.
Best for 2-Inch PVC/ABS – SP20285 Horizontal Vent Termination Kit
If you need a tankless water heater exhaust vent kit for a 2-inch PVC or ABS setup, the SP20285 Horizontal Vent Termination Kit is a practical, low-profile option. It’s designed to terminate intake and exhaust lines cleanly through an outside wall, helping keep high-efficiency systems vented safely while improving curb appeal.
Best For: Homeowners or installers working with 2-inch vent piping who want a simple horizontal termination solution for tankless gas water heaters or high-efficiency furnaces.
Pros:
- Fits 2-inch PVC and ABS vent pipe systems
- Low-profile design hides intake and exhaust pipes for a cleaner exterior
- Includes screws for a straightforward install
- Suitable for horizontal wall or vertical roof applications
Cons:
- Only works with 2-inch piping, so compatibility must be checked first
- Not a universal vent kit for larger or different pipe sizes
This is a solid pick if your tankless water heater exhaust vent kit needs are centered on a 2-inch, outside-wall termination and a neater finished look. Just verify pipe dimensions and cut lengths before buying to avoid installation issues.
Best for Easy DIY Install – FOGATTI Stainless Steel Vent Kit
If you need a tankless water heater exhaust vent kit that balances durability with straightforward installation, this FOGATTI set is a practical pick. It includes the key parts needed for a horizontal vent setup and uses T304 stainless steel for better corrosion resistance and heat handling.
Best For: DIY homeowners and installers who want a simple, corrosion-resistant vent solution for compatible gas tankless water heaters.
Pros:
- T304 stainless steel construction helps resist corrosion and high heat.
- Horizontal termination design is built for residential tankless water heater exhaust routing.
- Simple assembly with included elbow and chimney rain cap for a more complete kit.
- Works with a range of gas tankless water heater models when sizing matches.
Cons:
- Diameter compatibility must be checked carefully before ordering.
- Not a universal solution for every venting layout or install configuration.
- May require additional vent components for longer or more complex runs.
Overall, this tankless water heater exhaust vent kit stands out for buyers who want a durable stainless option that is easy to assemble and well-suited to standard horizontal venting jobs.
Best for Through-Wall Installs – Rheem RTG20280-1 Horizontal Vent Kit
If you need a tankless water heater exhaust vent kit for a Rheem non-condensing indoor unit, this ProTech termination kit is built for straightforward horizontal through-the-wall venting. The stainless steel parts, included wall plate, and 94-degree elbow make it a practical choice when you want a clean, code-friendly vent exit with the right fit for compatible Rheem EcoSense systems.
Best For: Homeowners or installers working with compatible Rheem tankless gas units and a horizontal wall-termination setup.
Pros:
- Stainless steel construction helps resist corrosion and wear.
- Includes a 12-inch wall plate and mounting screws for a more complete install.
- Adjusts for wall thicknesses up to 10 inches.
- 3 x 5 inch vent sizing suits compatible non-condensing tankless heaters.
Cons:
- Made for specific Rheem EcoSense direct-vent units, so compatibility is limited.
- Not a universal vent kit for all tankless water heater exhaust vent kit applications.
- Best for horizontal termination only, not flexible for other vent layouts.
For the right Rheem setup, this kit covers the core parts you need without unnecessary extras. If your installation matches the specs, it’s a solid tankless water heater exhaust vent kit option for a durable, direct horizontal termination.
Best Simple Pick – GASLAND 3" Stainless Vent Kit
If you need a tankless water heater exhaust vent kit for a 3-inch gas unit, this GASLAND set is a practical match. It includes the core horizontal vent pieces, wall thimble, and termination hood in one package, so you can build out a safer exhaust path without sourcing every part separately.
Best For: GASLAND tankless water heater owners and any buyer needing a 3" venting solution with a straightforward, modular layout.
Pros:
- T304 stainless steel construction for better corrosion and heat resistance
- Modular parts can be assembled to fit different vent lengths
- Includes the main pieces needed for a horizontal exhaust run
- Compatible with many GASLAND models and other 3" exhaust-port heaters
Cons:
- Only fits systems that require a 3" exhaust diameter
- May still require additional venting parts depending on your install
- Best suited to horizontal routing, not every vent configuration
This tankless water heater exhaust vent kit stands out for convenience and compatibility rather than complexity. If your installation matches the 3-inch spec, it offers a solid, durable starting point for a clean vent run.
How We Picked the Best Tankless Water Heater Exhaust Vent Kit
We prioritized compatibility, vent size, build quality, and installation practicality. For a Tankless Water Heater Exhaust Vent Kit, the most important factor is matching the heater’s required vent diameter and venting style. We also looked for corrosion-resistant materials like stainless steel, secure termination hardware, and options suited to direct-vent or horizontal termination installs.
Quick Comparison
Most of the products in this roundup fall into two groups: 2-inch vent termination kits and 3-inch stainless steel vent kits. In general, 2-inch kits are more common for certain high-efficiency and furnace-related applications, while 3-inch kits are typically used with specific tankless models that call for larger venting. Always verify the manufacturer’s instructions before buying.
Key Buying Factors for a Tankless Water Heater Exhaust Vent Kit
Size and Compatibility
Start with the heater manual. The wrong vent diameter can cause installation problems or unsafe operation. Check both the pipe size and whether the system needs a horizontal termination, direct vent, or a specific elbow configuration.
Material and Corrosion Resistance
Stainless steel is a strong choice for durability, especially in venting applications where moisture and heat are constant factors. If your unit produces condensate or is installed in a harsh environment, material quality matters even more.
Included Parts
Look closely at what the kit includes: elbow, termination hood, pipe length, screws, rain cap, or wall termination hardware. A more complete kit can simplify the install and reduce the chance of missing parts.
Installation Location
Wall clearance, exhaust direction, and local code requirements all affect what will work. A horizontal vent termination kit may be ideal for exterior wall exits, while other layouts may require different fittings or additional vent components.
Who Should Buy Which Tankless Water Heater Exhaust Vent Kit?
If you need a straightforward exterior wall termination, a 2-inch horizontal kit may be the best fit. If your heater specifies 3-inch venting, choose a stainless steel 3-inch kit built for that exact size. Buyers who want the easiest setup should favor kits with clearly listed compatibility and a fuller hardware package. For any Tankless Water Heater Exhaust Vent Kit purchase, the safest approach is to match the venting requirements in the installation manual before ordering.
