Why choose HepvO? The benefits of a waterless plumbing trap

min read time
2021-01-06 23:00:00

As any good plumber knows, traditional water traps can lose their seal due to evaporation, siphonage, leaking or movement. An innovative waterless trap, HepvO doesn't encounter any of these issues and is suitable for use on a range of sanitary appliances. 


What is HepVO?

HepVO is a unique waterless self-sealing waste valve that prevents the escape of foul sewer air from waste discharge systems and actively maintains the pressure equilibrium in soil and waste installations.

When you need to prevent foul sewer gases from entering a building, HepVO valve can be installed as an alternative to a conventional plumbing water trap.


How does HepVO work?

As a dry-sealing valve, HepVO uses a purpose-designed membrane to create an airtight seal between the living space and the drainage system. The self-sealing valve opens under the water pressure of an appliance emptying and closes to form a tight seal after the appliance has discharged under normal atmospheric conditions.

Watch our overview video to find out more about how HepVO works.



Why use HepvO?

Traditional water traps can sometimes lose their seal due to evaporation, siphonage, leaking or movement, but since HepVO doesn’t rely on water to create a seal, it doesn’t carry these risks of failure.

It also offers a great range of other benefits for both installers and end-users:

  • HepVO can be installed vertically or horizontally, making it a perfect solution for a range of requirements, from wash hand basins to kitchen sinks and showers
  • The unique design means there’s no U-bend in which waste material can potentially build up causing blockages and smells. Plus, tests have proven that not even soaps, detergents, hair or food particles can block the valve.



  • Hep vO admits air into the drainage system, so there’s no need to add a 40mm air admittance valve for branch ventilation to relieve negative pressures, which means you don’t get the gurgling noises you get with a traditional water trap!
  • There’s no chance of evaporation, so it’s great for infrequent use such as in holiday lets, guest bathrooms, or park homes. Hep vO also performs successfully in motor homes and even boats where water traps can lose their seal through movement and vibration.
  • Hep vO will perform under back pressures which are 10 times greater than those experienced in a typical soil and waste system.


Learn more about HepvO

HepvO is suitable for use on sanitary appliances and can also be installed on discharge pipework from unvented domestic hot water systems and condensate lines from boilers and air conditioning units. Click here to find out more


Where to buy HepvO

Hep vO is part of our Osma Above Ground range. Visit our Stockist Locator to find your local merchant.