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Most cities were not designed to handle the current climate and environmental challenges. So how can we help our cities become more climate resilient while better securing water resources?
How can we help our cities become more climate resilient while better securing water resources?

Wavin HepVO Self-Sealing Waste Valve

Waste Solutions

Wavin HepVO is a self-sealing waste valve that uses a soft silicone rubber membrane to create the seal instead of water, eliminating foul odors in HVAC drain waste vent lines and the health risks of stagnant water in plumbing systems.

Wavin HepVO is an ideal alternative to conventional P-traps for tight spaces and infrequent-use installations such as vacation homes, condominiums, cabins, guest bathrooms, and bar sinks as well as in motor homes, tiny houses, recreational vehicles, boats, yachts, and concession trailers. The Wavin HepVO system includes compatible in-line adaptors and angle adapters.


Wavin HepVO is a highly effective alternative to a conventional p-trap

Available in 1¼” and 1½” dimensions, Wavin HepVO can be installed either vertically or horizontally with an angle adaptor. For all drain lines with low, intermittent, or seasonal use, Wavin HepVO is a highly effective alternative to a conventional p-trap. Already in use in North America in RVs and boats, Wavin HepVO technology is now approved for residential and commercial use from the 2024 Uniform Plumbing and Mechanical Codes for HVAC applications. 

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Wavin provides a complete solution in combination with the BOW ABS DWV Foam Core piping system.

Bow ABS DWV Foam Core (Coextruded ABS Cellular Core) pipe is used for plumbing drain, waste, and vent applications. The pipes and fittings are available in 1-1/4 inch to 6-inch nominal diameters.

  • Made in 3/8”, ½”, ¾” and 1” nominal sizes.
  • Available in coils and in straight lengths.
  • The tubing is made to CTS (Copper Tube Size) outside dimensions and an SDR (Standard Dimension Ratio) of 9.
ABS Fittings Price List PDF ABS Fittings Price List Excel ABS Backwater Valbes Spec Sheet

Frequently Asked Questions

Is Wavin HepVO used in addition to a conventional trap?

NO, unlike other products which prevent foul odors entering the living space, HepVO is used instead of a conventional water-seal trap.

When using a Wavin HepVO in place of a P-trap in a residential or commercial building what should I do about venting?

The full venting requirements of the applicable Plumbing Code shall still be followed, irrespective of whether a P-trap or a Wavin HepVO is installed.

Can I use drain cleaning chemicals?

Wavin HepVO is resistant to standard caustic-based drain cleaners. It is also resistant to acid-based cleaners with concentrations up to 10%. When flushing with higher concentrations of acid based cleaner, the valve must be removed before the operation. After any maintenance, it is recommended that the valve is flushed through with clean water.

Wavin HepVO is a new product to me - how can I be confident that it will provide good performance once installed? 

Wavin HepVO is new to the North American market, but it is not a new product. It has been in volume production in the UK since 1997 and it is widely used in Europe, Australia and the Far East. It has attained numerous international approvals against very demanding standards and has achieved an enviable track record of trouble-free performance.

Will Wavin HepVO promote better hygiene by stopping the escape of foul sewer air into habitable spaces?

YES - The valve has been proven to perform under conditions in which traditional water seal traps are vulnerable to failure. It will continue to perform under back pressures 10 times greater than those experienced in correctly designed soil and waste systems.

Does the airtight seal break down if a strand of cloth or hair collects in the strainer and falls down between the faces of the valve?

NO – Wavin HepVO has undergone extensive foreign body testing (ASME A112.18.8). Tests show that the valve will maintain an airtight seal around an obstruction such as hair, fabric strands or spaghetti.

What is the life expectancy of Wavin HepVO?

Installed correctly can be expected to have a life expectancy at least equivalent to current water sealed traps. In addition, Wavin HepVO is guaranteed against defects in materials or manufacturing for a period of 3 years.

Will Wavin HepVO block easily for example if fat is discharged through it?

NO - Extensive testing has shown that Wavin HepVO is less prone to blockage than traditional water seal traps. Note: because the ‘straight through’ design of Wavin HepVO does not trap debris discharged through the waste fixture care should be taken with jewelry and other valuables.

Will the seal be maintained even when the fixture hasn’t been used for some time?

YES - Wavin HepVO does not depend on a water seal and so it will continue to maintain a seal whether a fixture never gets used or is used very infrequently.

Does the valve make a noise?

Under normal conditions Wavin HepVO operates silently, unlike normal traps that are prone to ‘gurgle’.

Will Wavin HepVO support microbiological growth?

NO - The materials used to manufacture Wavin HepVO will not support microbiological growth, for example mold and mildew.

Building healthy and sustainable environments

Safe and Efficient

Future generations face a 40% shortfall between water supply and demand. Alongside other experts, Wavin is working to deliver safe and clean water security through enhanced rainwater reuse, the digitalization of water management and more secure and durable piping.

Sanitation and Hygiene

Outdated sewer systems are overwhelmed by a triple whammy of urbanization, population growth and climate change. We are working towards a healthier future with long-lasting sanitation solutions that deliver greater capacity, fewer leaks, less clogging and better monitoring. 

Climate Resilient Cities

Smarter systems are needed to meet the five big challenges our cities face: floods, droughts, heat stress, ground water depletion and surface-water pollution. From roof to river, we are helping with connected water capture, attenuation, cleaning, reuse, and transportation solutions to make cities climate resilient. 

Building Performance

Constrained by time, cost, and product sourcing challenges, many of today’s buildings fail to deliver on their expected performance. Through improved digital modelling, we can help our partners predict time and resource needs throughout the building process and provide intelligent solutions for better urban living.