Should an air admittance valve rattle?

Author: Prof. Craig Cremin  |  Last update: Wednesday, June 4, 2025

To see if the AAV is working properly, take the valve off and shake - if you shake hard enough you should hear the diaphragm rattling. If you hear no noise the AAV may have failed. Additionally, smelling sewer gas is another sign that the AAV has failed in the open position.

Do air admittance valves make a noise?

If it's doing its job correctly, the AAV should make a noise when the toilet is flushed. It's like a low frequency rumble as the rubber disk bobs up and down allowing air to be admitted to the stack so the negative pressure in the stack does not suck the water out of the traps of the shower, basin, sinks, etc.

What are the symptoms of a faulty air admittance valve?

An air admittance valve leaving behind clogs and sewer odor is faulty, so be sure to find your receipt if you still have it and take the valve back as soon as you see that it is not working.

What is the life expectancy of an air admittance valve?

Air admittance valves have a typical life expectancy of 20-30 years, so if you start to have issues with sewer gases or smells being released around your sink or in the attic-wherever installed- the air admittance valve could be faulty or failed and should be replaced as soon as possible.

What is the downside to an air admittance valve?

The main problem with using an Air Admittance Valve instead of a Soil Vent Pipe, as discussed earlier, is that by preventing the gases from escaping through the top of the soil stack you are causing them to be forced down into the main drains and sewer system instead.

Air admittance valves for plumbing venting explained, [just over 4 minutes]

How to tell if studor vent is bad?

Signs of that the Sure-Vent is not operating as intended, are foul odors. If you smell foul odors (sewer smell) near a plumbing fixture which has a Sure-Vent installed, this means the Sure-Vent is not closing properly to create a positive seal and should be replaced.

Why is studor vent illegal?

The Studor vent lets that air to be sucked in the pipe during water flow but doesn't let sewer gas escape out. Code is the thing that determines pipe size and also water flow. Hence no studor vents are permitted to toilets because more air is required to keep water flow going with more waste added to the toilet.

Where is the best place to put an air admittance valve?

AAV location

An AAV should be located within the maximum developed length permitted for the vent. It must be located a minimum of 4” above the horizontal branch drain, 6” above any insulation material and within 15 degrees of vertical.

Can water come out of an air admittance valve?

In order for a liquid to come out, air must come in. All DWV plumbing systems require at least one vent penetration through the roof line, which allows air to enter the system, while also permitting sewer gas to escape.

Why does my air admittance valve smell?

If there is an issue with pressure in the pipework system and not enough air is able to be drawn in, it can cause problems such as waste water coming back up from the traps. If you've ever smelt that “drain smell” coming from a plughole then this is likely what is happening as it stops the traps from working correctly.

Do you glue air admittance valve?

Depending on the type of fitting, glue or screw the AAV in place. Look to the manufacturer's directions if you need additional assistance.

What are the rules for air admittance valves?

Air admittance valves are generally placed on a soil pipe that is a minimum of 200mm above the highest water entry point – i.e. the highest point wastewater will reach within a soil pipe. They are most commonly installed at the end of a soil pipe, but can also be installed inline, using a branch.

Where are air admittance valves not allowed?

Air admittance valves are not permitted in spaces where pressure conditions adversely affect the valve's operation. They are also not allowed in concealed wall and ceiling spaces used as plenums as part of an air distribution system that is under negative or positive pressure.

Why are my valves noisy?

Over time, the valve guides and seals can wear out or crack, causing noise and oil consumption. Worn valve guides can cause the valve to wobble or chatter in the head, creating a ticking or knocking sound. Damaged valve seals can cause oil to leak past the valve stem, creating a blue smoke or a burnt oil smell.

Can an air admittance valve fail?

Yes, there are some occasions when a Durgo / air admittance valve failure is possible.

Why is water coming out of air valve?

This is because most air release valves seal around 25 – 30 psi unless a special soft seat is provided. So when the pipeline is filling and pressurizing, your air valve is exhausting both air and water into the exhaust pipe.

Will an air admittance valve help a slow drain?

These valves not only save space but also help keep sewer gas out of your home, promoting cleaner air. If you notice slow drains or gurgling sounds from sinks, it might mean there's negative air pressure in your drainage system, and that's the ideal time for these valves to be beneficial.

Are air admittance valves a good idea?

An AAV can significantly reduce the number of venting materials needed in a plumbing system. That's money in the pocket of the plumber. They also allow greater flexibility in the layout of plumbing fixtures and reduce long-term roof maintenance. If we don't have a hole in the roof, it's easier to maintain it.

Do I need an AAV under the sink?

Some sinks will give hints that an AAV is necessary. A sink that gurgles loudly, for example, or one that drains very slowly even though there are no clog issues, might be doing so because of negative air pressure in the lines. Adding an AAV often resolves these issues.

Does an air admittance valve replace a vent?

Air Admittance Valves (AAV) — Oatey ®Sure-Vents® — are mechanical devices installed to a plumbing fixture, replacing a secondary vent. These valves allow one-way ventilation, removing the need to connect to an existing venting system or run a separate, potentially unsightly ventilation system.

What is the difference between in line vent and air admittance valve?

Automatic air vents are spring type devices often referred to as in-line or cheater vents, while air admittance valves have no spring. Air admittance valves are more expensive and are approved in many jurisdictions where in-line and cheater vents are not because of their moving parts (springs).

Can an air admittance valve be boxed in?

Where an AAV is enclosed in a boxing the boxing should be ventilated. The use of ventilation grilles, discreet gaps around the boxing or ventilation of the boxing into a ventilated roof void are some acceptable methods of providing ventilation.

Can you vent a toilet with an air admittance valve?

Yes, an air admittance valve can be used to vent a toilet. This valve is a device designed to allow air to enter the plumbing drainage system to balance the pressure, keeping water from getting pulled out from traps in the plumbing fixtures.

What height should AAV be installed?

The stack-type AAV shall be located not less than 6 inches (152 mm) above the flood-level rim of the highest fixture being vented. The AAV shall be located within the maximum developed length permitted for the vent.

Previous article
How do I know if I can tumble dry something?
Next article
How many amps does a water softener use?