Direct answer: these vent pipes and concentric vent kits are designed to safely exhaust combustion gases from tankless water heaters and nearby stoves, with options for easy installation, corrosion resistance, and adjustable wall fittings. The best choice depends on your vent size, wall thickness, and installation space. This guide highlights five suitable products, clarifying who each is best for and why. Each option aims to ensure secure venting, reduce leaks, and maintain proper airflow for safe operation.
Buyer’s quick reference:
- Best overall for versatile installations: Concentric vent kit with multiple adapters and adjustable wall thimble.
- Best value for single-piece stainless vent: Premium 304 stainless vent pipe kit.
- Best for quick installs: 1-step connection vent pipes from Rheem lines.
- Best for wall-penetration flexibility: 4.7″–9.1″ adjustable wall thimble kit.
- Best for standard 12-inch conduit runs: 12-inch concentric vent pipe option.
| Product | Key Benefit | Best For |
|---|---|---|
| Vent Kit for Tankless Water Heater and Wood Stove | Sturdy 304 stainless, corrosion resistant | Homeowners needing a complete installation kit |
| Rheem RTG20270D Tankless 36 in. Concentric Vent Pipe | One-step connection, leak-proof | Fast installs |
| Rheem RTG20270C Tankless 24 in. Concentric Vent Pipe | Stainless steel, easy fit | Medium-length runs |
| Concentric Vent Kit 2.36″-3.15″ Pipes with Wall Thimble | Adjustable wall penetration | Varied wall thicknesses |
| Rheem RTG20270B Tankless 12 in. Concentric Vent Pipe | Reliable gasket, simple install | Short runs |
Vent Kit for Tankless Water Heater and Wood Stove
Product: Vent Kit for Tankless Water Heater and Wood Stove
Brand: VATTCEEL Store
URL: https://www.amazon.com/dp/B0FVLKR311?tag=furnacesrevie-20
Features: Premium 304 stainless steel construction; diameter 2.36 inches, length 14.56 inches; corrosion resistant; designed for venting gas water heaters and wood stoves; enhances safety and efficient venting by removing smoke and gases securely.
Best for: Homeowners needing a complete vent installation kit with robust corrosion resistance for combined appliance venting. This unit is well-suited when a durable, all-in-one solution is preferred.
Why selected: It combines common sizing with stainless steel durability to ensure long-term performance in high-heat exhaust environments.
Caution: Verify your appliance’s exact vent diameter and length requirements before purchasing.
Rheem RTG20270D Tankless 36 in. Concentric Vent Pipe
Product: Rheem RTG20270D Tankless 36 in. Concentric Vent Pipe
Brand: Rheem
URL: https://www.amazon.com/dp/B0F7Y6SYRB?tag=furnacesrevie-20
Features: Fast installation with a 1-step connection; leak-proof gasket design; durable stainless steel construction for long-lasting use.
Best for: Quick-install projects where speed plus a secure seal are priorities. This is a practical choice for homeowners upgrading existing venting or completing new tankless setups.
Why selected: The combination of simple connection and reliable gasket helps reduce installation time and potential leaks.
Caution: Ensure the 36-inch length matches your vent run requirements before ordering.
Rheem RTG20270C Tankless 24 in. Concentric Vent Pipe
Product: Rheem RTG20270C Tankless 24 in. Concentric Vent Pipe
Brand: Rheem
URL: https://www.amazon.com/dp/B0F7Y63W6Q?tag=furnacesrevie-20
Features: Fast, easy installation with 1-step connection; leak-proof gasket; stainless steel construction for durability.
Best for: Medium-length vent runs where a dependable, corrosion-resistant option is needed without extra adapters. This is suitable for typical mid-range installations.
Why selected: The straightforward installation and robust gasket design support reliable performance with minimal effort.
Caution: Confirm wall thickness and vent diameter compatibility with your unit.
Concentric Vent Kit 2.36″-3.15″ Pipes with Wall Thimble
Product: Concentric Vent Kit for Tankless Water Heater 2.36″-3.15″ Pipes
Brand: (Not listed)
URL: https://www.amazon.com/dp/B0H13YQDSW
Features: Fits 2.36″ to 3.15″ vent pipes; includes adapters (3.15″, 2.76″, 2.36″); compatible with most tankless vent kits and direct vent wall thimbles; sturdy 1mm 304 stainless steel; adjustable for wall thickness 4.7″–9.1″ via telescoping design.
Best for: Flexible installation across varied vent pipe sizes and wall thicknesses. This is ideal when you need adjustability and broad compatibility in one kit.
Why selected: The kit’s adaptability minimizes the need for multiple separate components, reducing installation complexity.
Caution: The telescoping design may require precise alignment to ensure a proper seal in some configurations.
Rheem RTG20270B Tankless 12 in. Concentric Vent Pipe
Product: Rheem RTG20270B Tankless 12 in. Concentric Vent Pipe
Brand: Rheem
URL: https://www.amazon.com/dp/B0F7Y8SXHV?tag=furnacesrevie-20
Features: Fast installation with a 1-step connection; leak-proof gasket; stainless steel construction for durability.
Best for: Short vent runs where a compact, reliable pipe is needed. It’s a solid choice for tight spaces or compact installations.
Why selected: The combination of quick setup and durable materials supports dependable use in limited spaces.
Caution: Verify that a 12-inch run meets your equipment’s venting requirements before purchasing.
Buying Guide
What to consider when choosing vent pipes for tankless water heaters:
- Vent size compatibility: Match the pipe diameter (commonly 2.36″ to 3.15″) to your heater’s exhaust outlet and any adapters needed.
- Material durability: Stainless steel (304 grade) offers corrosion resistance and high-temperature tolerance; ensure the material is rated for outdoor or indoor use as required.
- Installation length: Measure required run length and consider whether a single piece or modular kit provides easier installation and fewer joints.
- Wall penetration: Evaluate wall thickness and available space. Adjustable wall thimbles and telescoping designs help fit varied walls and improve sealing.
- Sealing and gasket quality: A leak-proof gasket reduces the risk of exhaust leaks; ensure compatibility with your venting system.
- One-step connection systems: These simplify installation but confirm they fit your specific model and vent configuration.
- Ease of future service: Consider components that are easy to replace or extend if you upgrade or relocate the heater.
FAQ
- What vent size is typical for tankless water heaters?
Most systems use 2.36″ to 3.15″ diameter vents, but always check the manufacturer specifications for your model. - Are stainless steel vent pipes safer for high temperatures?
Yes. Stainless steel offers better corrosion resistance and can handle high-temperature exhaust common with gas-fired units. - Is a wall thimble necessary?
A wall thimble protects the wall penetration from heat and corrosion and helps create a tight seal around the vent pipe. - Can I mix vent pipe brands?
Mixing brands is possible if the sizes and adapters match, but using a matched kit often ensures better compatibility and a tighter seal. - Do I need a professional for installation?
Installation complexity varies. Simple, one-step connection pipes may be DIY-friendly, while adjustable wall kits may benefit from professional installation for optimal sealing. - What is a concentric vent pipe?
A concentric vent combines intake and exhaust in a single assembly, reducing space needs and simplifying installation in tight areas.