Skip to content
Enjoy fast and free shipping on all orders over $89! Contact us (855) 424-4376
Enjoy fast and free shipping on all orders over $89! Contact us (855) 424-4376

Tankless Venting

Tankless install and vent kits to finish gas (NG/LP) and high-output electric water heaters cleanly and to spec. Shop concentric and twin-pipe venting, wall/roof terminations, thimbles and flashings, pipe covers, isolation/flush valves, and condensate parts—then match diameters and lengths to your model’s tables.

Shop by need

  • Concentric vent kits: coaxial intake/exhaust with horizontal or vertical terminations
  • Twin-pipe venting: separate intake and exhaust in PVC/CPVC/PP (per manual/code)
  • Terminations & adaptors: low-profile wall caps, roof cones, rain caps, conversion adaptors
  • Pass-through & sealing: wall thimbles, firestops, roof flashings, sealant and gaskets
  • Lengths & fittings: straight pipe, long/short-radius 45°/90° elbows, support clamps
  • Pipe covers & mounts: trim covers, brackets, stand-off kits, intake screens
  • Water/gas hook-up: isolation/flush valve sets, flexible gas connectors, shut-off valves
  • Condensate: traps, hose kits, pumps, and neutralizers for condensing units

Quick choosing guide

  1. Confirm model & type: indoor vs outdoor; condensing vs non-condensing. Use only vent materials approved by the manufacturer and local code (e.g., PVC/CPVC/PP for many condensing models; Category III stainless for some non-condensing).
  2. Pick vent style: Concentric simplifies wall/roof penetrations; twin-pipe is flexible for long runs or existing chases.
  3. Size the diameter: choose 2", 3", or 4" per the spec sheet. Calculate total equivalent length (add elbows) and stay within limits.
  4. Plan termination: horizontal or vertical, with code clearances to windows, doors, and grade. For condensing exhaust, pitch the vent back to the heater to drain condensate.
  5. Complete the kit: thimble/firestop, flashing, required adaptors, support hardware, pipe cover, and—on condensing models—condensate drain and neutralizer.
  6. Hook up water & gas: add isolation/flush valves, sediment/scale protection, a listed gas shut-off and connector, and a nearby outlet if the unit needs power.


  •

    Rinnai - MIVK-T-LW - Matsui Plumbing Isolation Valve Kit

    Rinnai
    $ 93.00 - $ 93.00
    $ 93.00
    $ 93.00 - $ 93.00
    $ 93.00

    Rinnai Isolation Valve Kit The Rinnai MVIK-T-LW tankless water heater valve kit facilitates a streamlined, two-step installation process for your ...

    View full details
    $ 93.00 - $ 93.00
    $ 93.00
    $ 93.00 - $ 93.00
    $ 93.00
  • Rinnai - Rinnai Universal Horizontal Termination Kit 11.5" 223181 - - Water Heater Venting - Big Frog Supply - 2
    Rinnai - Rinnai Universal Horizontal Termination Kit 11.5" 223181 - - Water Heater Venting - Big Frog Supply - 1

    Rinnai 223181 Non-Condensing Universal Horizontal Termination Kit 11.5"

    Rinnai
    $ 96.19 - $ 96.19
    $ 96.19
    $ 96.19 - $ 96.19
    $ 96.19

    Rinnai Universal Horizontal Termination Kit The Rinnai 223181 Non-Condensing Horizontal Termination Kit is an 11-1/2” universal venting solution th...

    View full details
    $ 96.19 - $ 96.19
    $ 96.19
    $ 96.19 - $ 96.19
    $ 96.19
  • Rinnai - Rinnai 21" Horizontal Termination Kit for Condensing Units 223177PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 223177PP - 21" Horizontal Termination Kit for Condensing Units

    Rinnai
    $ 114.00 - $ 114.00
    $ 114.00
    $ 114.00 - $ 114.00
    $ 114.00

    Rinnai's 21 inch horizontal termination kit finishes the route for your venting on a Rinnai tankless water heater. The 223177PP pipe is made specif...

    View full details
    $ 114.00 - $ 114.00
    $ 114.00
    $ 114.00 - $ 114.00
    $ 114.00
  • Rinnai - Rinnai Vent Pipe Extension 39" for Condensing Units 224080PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 224080PP - Vent Pipe Extension 39" for Condensing Units

    Rinnai
    $ 58.00 - $ 58.00
    $ 58.00
    $ 58.00 - $ 58.00
    $ 58.00

    Rinnai's 39 inch vent pipe extension helps route venting for your Rinnai tankless water heater. The 224080PP pipe is made specifically for Condensi...

    View full details
    $ 58.00 - $ 58.00
    $ 58.00
    $ 58.00 - $ 58.00
    $ 58.00
  • Rinnai - Rinnai Pipe Cover Enclosure for Luxury Series PCD03-SM2 - - Water Heater Covers - Big Frog Supply
    Sold out

    Rinnai - PCD03-SM2 - Pipe Cover Enclosure for Luxury Series

    Rinnai
    $ 200.00 - $ 200.00
    $ 200.00
    $ 200.00 - $ 200.00
    $ 200.00

    Rinnai cover enclosure for luxury series tankless water heaters. Cover your pipes to prevent damage, heat, cold from the pipes. This Cover fits w...

    View full details
    $ 200.00 - $ 200.00
    $ 200.00
    $ 200.00 - $ 200.00
    $ 200.00
    Sold out
  • Rinnai - Rinnai Universal Horizontal Termination Kit 21" 223182 - - Water Heater Venting - Big Frog Supply

    Rinnai - 223182 - Universal Horizontal Termination Kit 21"

    Rinnai
    $ 114.99 - $ 114.99
    $ 114.99
    $ 114.99 - $ 114.99
    $ 114.99

    Long termination kit for Rinnai tankless water heater venting in the shape of an L to go outside of side wall. Inner exhaust material is aluminum a...

    View full details
    $ 114.99 - $ 114.99
    $ 114.99
    $ 114.99 - $ 114.99
    $ 114.99
  • Rinnai - Rinnai Euro White Pipe Cover Enclosure for Ultra Series PCD07-EW - - Water Heater Covers - Big Frog Supply

    Rinnai PCD07-EW Euro White Pipe Cover Enclosure for RUS Ultra Series Tankless Water Heaters

    Rinnai
    $ 246.95 - $ 246.95
    $ 246.95
    $ 246.95 - $ 246.95
    $ 246.95

    Rinnai cover enclosure in European White color for ultra series tankless water heaters. Cover your pipes protecting them with this cover. SKU: PCD0...

    View full details
    $ 246.95 - $ 246.95
    $ 246.95
    $ 246.95 - $ 246.95
    $ 246.95

  • Rinnai - 107000284 - Isolation Valve Kit Next Gen Replacement for Sensei Models

    Rinnai
    $ 99.99 - $ 99.99
    $ 99.99
    $ 99.99 - $ 99.99
    $ 99.99

    Rinnai Isolation Valve Kit Next Gen Replacement for Sensei Models 107000284

    $ 99.99 - $ 99.99
    $ 99.99
    $ 99.99 - $ 99.99
    $ 99.99
  • Rinnai - Rinnai Vent Pipe Extension 39" 224053 - - Water Heater Venting - Big Frog Supply

    Rinnai - 224053 - Vent Pipe Extension 39"

    Rinnai
    $ 78.00 - $ 78.00
    $ 78.00
    $ 78.00 - $ 78.00
    $ 78.00

    39" vent pipe extension for your Rinnai tankless water heater venting. Inner exhaust material is aluminum and outer intake material is plastic. Pa...

    View full details
    $ 78.00 - $ 78.00
    $ 78.00
    $ 78.00 - $ 78.00
    $ 78.00

  • Rinnai - 107000639 - Dedicated Return & Isolation Valve Kit

    Rinnai
    $ 0.00 - $ 0.00
    $ 0.00
    $ 165.53
    $ 165.53 - $ 165.53
    $ 165.53

    Valve kit including tee, drain valve, pressure relief valve, check valve & isolation valves (cold & hot) to simplify set-up of a dedicated ...

    View full details
    $ 0.00 - $ 0.00
    $ 0.00
    $ 165.53
    $ 165.53 - $ 165.53
    $ 165.53
  • Rinnai - Rinnai 38" Roof Discharge for Condensing Units 184162PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 184162PP - 38" Roof Discharge for Condensing Units

    Rinnai
    $ 110.00 - $ 110.00
    $ 110.00
    $ 110.00 - $ 110.00
    $ 110.00

    Rinnai roof discharge 38" for condensing ultra series tankless water heaters. SKU: 184162PP Color of product may differ from image. This Venting ...

    View full details
    $ 110.00 - $ 110.00
    $ 110.00
    $ 110.00 - $ 110.00
    $ 110.00
  • Sold out

    Rinnai - PCD03-SM2-BP - Bottom Plate Tankless Water Heater Accessories

    Rinnai
    $ 58.00 - $ 58.00
    $ 58.00
    $ 58.00 - $ 58.00
    $ 58.00

    Features: Bottom plate for external value series Compatible with Rinnai models: RL75EN,RL75EP,RL94EN,RL94EP Manufacturer warranty: 5 Years Specif...

    View full details
    $ 58.00 - $ 58.00
    $ 58.00
    $ 58.00 - $ 58.00
    $ 58.00
    Sold out
  • Rinnai - Rinnai Vent Pipe Extension 19.5" for Condensing Units 224079PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 224079PP - Vent Pipe Extension 19.5" for Condensing Units

    Rinnai
    $ 49.00 - $ 49.00
    $ 49.00
    $ 49.00 - $ 49.00
    $ 49.00

    Rinnai's 19.5 inch vent pipe extension helps route venting for your Rinnai tankless water heater. The 224079PP pipe is made specifically for Conden...

    View full details
    $ 49.00 - $ 49.00
    $ 49.00
    $ 49.00 - $ 49.00
    $ 49.00
  • Rinnai - Rinnai Vent Pipe Extension 10" 224051 - - Water Heater Venting - Big Frog Supply

    Rinnai - 224051 - Vent Pipe Extension 10"

    Rinnai
    $ 50.00 - $ 50.00
    $ 50.00
    $ 50.00 - $ 50.00
    $ 50.00

    10" vent pipe extension for your Rinnai tankless water heater venting. Inner exhaust material is aluminum and outer intake material is plastic. Pa...

    View full details
    $ 50.00 - $ 50.00
    $ 50.00
    $ 50.00 - $ 50.00
    $ 50.00

  • Rinnai Pipe Cover PCD11-SHS fits Sensei RX

    Rinnai
    $ 0.00 - $ 0.00
    $ 0.00
    $ 231.00
    $ 231.00 - $ 231.00
    $ 231.00

    Rinnai Sensei RX Pipe Cover Give your tankless water heater installation a clean, finished look with the Rinnai PCD11-SHS Pipe Cover Enclosure. Thi...

    View full details
    $ 0.00 - $ 0.00
    $ 0.00
    $ 231.00
    $ 231.00 - $ 231.00
    $ 231.00
  • Rinnai - Rinnai Vent Pipe Extension 10" for Condensing Units 224087PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 224087PP - 10" Metal Pass Through Condensing Venting Plate

    Rinnai
    $ 39.00 - $ 39.00
    $ 39.00
    $ 39.00 - $ 39.00
    $ 39.00

    Rinnai's 10 inch vent pipe extension helps route venting for your Rinnai tankless water heater. The 224087PP pipe is made specifically for Condensi...

    View full details
    $ 39.00 - $ 39.00
    $ 39.00
    $ 39.00 - $ 39.00
    $ 39.00
  • Rinnai - Rinnai 90 Degree Vent Pipe Elbow for Condensing Units 224078PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 224078PP - 90 Degree Vent Pipe Elbow for Condensing Units

    Rinnai
    $ 44.00 - $ 44.00
    $ 44.00
    $ 44.00 - $ 44.00
    $ 44.00

    Rinnai's 90 degree elbow vent pipe helps route venting for your Rinnai tankless water heater. The 224078PP pipe is made specifically for Condensing...

    View full details
    $ 44.00 - $ 44.00
    $ 44.00
    $ 44.00 - $ 44.00
    $ 44.00
  • Rinnai - Rinnai 45 Degree Vent Pipe Elbow for CONDENSING Units 224077PP - - Water Heater Venting - Big Frog Supply

    Rinnai - 224077PP - 45 Degree Vent Pipe Elbow for CONDENSING Units

    Rinnai
    $ 61.00 - $ 61.00
    $ 61.00
    $ 61.00 - $ 61.00
    $ 61.00

    Rinnai's 45 degree elbow vent pipe helps route venting for your Rinnai tankless water heater. This 224077PP pipe is made specifically for Condensin...

    View full details
    $ 61.00 - $ 61.00
    $ 61.00
    $ 61.00 - $ 61.00
    $ 61.00
  • Rinnai - Rinnai 18" Roof Discharge Terminal 184118S - - Water Heater Venting - Big Frog Supply

    Rinnai - 184118S - 18" (above roof) Roof Discharge Terminal

    Rinnai
    $ 115.00 - $ 115.00
    $ 115.00
    $ 115.00 - $ 115.00
    $ 115.00

    Rinnai roof discharge 18" for non-condensing ultra series tankless water heaters. SKU: 184118S Color of product may differ from image. This ventin...

    View full details
    $ 115.00 - $ 115.00
    $ 115.00
    $ 115.00 - $ 115.00
    $ 115.00
  • Rinnai - Rinnai 90 Degree Elbow 224063 - - Water Heater Venting - Big Frog Supply

    Rinnai - 224063 - 90 Degree Elbow

    Rinnai
    $ 63.00 - $ 63.00
    $ 63.00
    $ 63.00 - $ 63.00
    $ 63.00

    This 90 degree elbow is for non-condensing (luxury and value series) Rinnai tankless water heaters. Rinnai 224063. Product color may differ from im...

    View full details
    $ 63.00 - $ 63.00
    $ 63.00
    $ 63.00 - $ 63.00
    $ 63.00
  • Rinnai - Rinnai Vent Pipe Extension 19.5" 224052 - - Water Heater Venting - Big Frog Supply

    Rinnai - 224052 - Vent Pipe Extension 19.5"

    Rinnai
    $ 71.00 - $ 71.00
    $ 71.00
    $ 71.00 - $ 71.00
    $ 71.00

    19.5" vent pipe extension for your Rinnai tankless water heater venting. Inner exhaust material is aluminum and outer intake material is plastic. ...

    View full details
    $ 71.00 - $ 71.00
    $ 71.00
    $ 71.00 - $ 71.00
    $ 71.00

  • Rinnai - 224356NPP - 2inch / 4 inch Condensing Roof Discharge Termination 20 in. Above Roof

    Rinnai
    $ 68.70 - $ 68.70
    $ 68.70
    $ 68.70 - $ 68.70
    $ 68.70

    For use with the following models: RU199i RU180i RU160i RU130i RUR199i RUR160i CU199i CU160i Material of Inner/Exhaust - Polypropylene Mater...

    View full details
    $ 68.70 - $ 68.70
    $ 68.70
    $ 68.70 - $ 68.70
    $ 68.70
  • Rinnai - Rinnai 45 Degree Elbows For Venting NON CONDENSING (2 Pack) 224050 - - Water Heater Venting - Big Frog Supply

    Rinnai - 224050 - 45 Degree Elbows For Venting NON CONDENSING (2 Pack)

    Rinnai
    $ 87.00 - $ 87.00
    $ 87.00
    $ 87.00 - $ 87.00
    $ 87.00

    45 degree elbows for your Rinnai tankless water heater venting. Inner exhaust material is aluminum and outer intake material is plastic. Part Numb...

    View full details
    $ 87.00 - $ 87.00
    $ 87.00
    $ 87.00 - $ 87.00
    $ 87.00

  • Rinnai - 229310NPP - 2inch / 4 inch Condensing Vent Pipe Extension, 39 Inches

    Rinnai
    $ 49.99 - $ 49.99
    $ 49.99
    $ 49.99 - $ 49.99
    $ 49.99

    For use with the following models: RU199i RU180i RU160i RU130i RUR199i RUR160i CU199i CU160i Material of Inner/Exhaust - Polypropylene Mater...

    View full details
    $ 49.99 - $ 49.99
    $ 49.99
    $ 49.99 - $ 49.99
    $ 49.99

Pro tips: Dry-fit and measure twice, support vents per the manual, and use the manufacturer’s approved cement or gasketed joints (no sealant on gasketed lock-rings). Maintain clearances, neutralize condensate, and keep a printout of your vent length calc with the install. After start-up, check for leaks, verify combustion settings, and run a full hot-water draw. Questions? Tell us model, fuel, vent path, and pipe size—we’ll recommend the right kit.

Related Articles

Rinnai SENSEI RX: How to Set the Gas Type (NG - LP) – Quick Installer Guide

Learn how to set Natural Gas or Propane on a Rinnai SENSEI RX tankless water heater: enter Parameter 10, save,...

5 Powerful Benefits of Upgrading to a Rinnai Tankless Water Heater

If your water heater’s age is kicking into the double digits, it’s time to consider replacing it. Rusty water and...

How to fix the Rinnai Error Code LC or 00 Scale Build-Up Problem?

Rinnai Error Code LC Scale Build-Up can cause your water heater to malfunction. Read on to learn how to fix...

How to Properly Install Rinnai Concentric Vent Kits: A Step-by-Step Guide

Learn how to properly install Rinnai concentric vent kits to ensure safe and efficient operation of your tankless water heater....

How to set up your Rinnai Central Wifi App

Smart Connect Allows you to connect your smart phone or tablet to the SENSEI® RX Series via Bluetooth®. Use the...

How Tankless Water Heaters Work

A tankless Rinnai water heater works by heating water on demand as it flows through the unit, rather than storing...

Properly Sizing a Tankless Water Heater

Tankless hot water heaters are an excellent choice for homeowners who want to save money on their energy bills while...

Choosing the right Tankless Electric Water Heater for your home.

In deciding on a Tankless Electric Water Heater there are three main factors. First is determining what application/install you are...

Why Every Home Needs a Wireless Controller for their Tankless Water Heater

Imagine having full control over your water heating system. Now, think about being able to monitor your tankless water heater...

Preventing Scale Build up in your Tankless Hot Water Heater

Scale build-up occurs when minerals and other impurities in the water accumulate on the heating element surfaces, impeding heat transfer...

Compare products

{"one"=>"Select 2 or 3 items to compare", "other"=>"{{ count }} of 3 items selected"}

Select first item to compare

Select second item to compare

Select third item to compare

Compare