OdorHog Vent Stack Pipe Filter 4 Sizes, Black ABS with Mushr

The Verdict

Stop Sewer Gas Before It Hits Your Nose — And Your Lungs

If you’re smelling rotten eggs near a bathroom vent pipe or catching whiffs of sewer gas that mysteriously vanish by the time the plumber arrives, the OdorHog vent stack filter is the fix you’ve been hunting. This isn’t an air freshener playing dress-up — it’s an activated carbon filter that physically traps the hydrogen sulfide and methane compounds that cause that unmistakable stink. With a 4.6-star average across 229 ratings, it’s earning real traction among homeowners and RV owners alike. Here’s what you need to know before you buy.

What’s in the Box and What You’re Working With

You get the filter housing pre-assembled in black ABS plastic — a UV-stabilized material that won’t chalk or crack after a few summers on the roof. The unit includes the activated carbon filter media, a stainless steel screen to keep critters and debris out, and the mushroom cap that snaps on top. The kit covers four pipe sizes (2", 3", 4", and 6") via a series of adapters, so you won’t be hunting for a separate fitting. As shown in the product image, the cap’s overhang is generous enough to keep horizontal rain from working its way down into the filter bed.

Real-World Performance: Does It Actually Kill the Smell?

Yes — and that’s the headline. The carbon media works by adsorption, pulling odor molecules out of the air as they rise up the vent stack. One buyer put it simply: “I could smell raw sewage in my backyard every time the wind shifted. Installed this on the roof vent, and the smell was gone within a day. Wish I’d done this years ago.” Another noted it solved a problem that two plumbers couldn’t diagnose: “The plumbers said my vent was fine, but the smell was real. This thing fixed it. Zero odor now.”

The catch is that the filter media has a finite life. Depending on how much airflow and odor volume your system produces, expect to swap the carbon cartridge every 6 to 12 months. Replacement cartridges run about $25–$35, which is worth it if it means not smelling sewage every time you walk outside — but it’s a recurring cost you should budget for.

Where It Falls Short (Honest Talk)

The biggest friction point is installation. The OdorHog is designed to be glued onto a cut section of pipe — it’s not a slip-over sleeve. If you’re retrofitting an existing vent stack, you’ll need to cut the PVC or ABS pipe with a hacksaw, deburr the edge, and cement the fitting on. That’s a 30-minute job for someone comfortable with basic plumbing, but it’s a non-starter if you’re strictly a “hand me a wrench and point me at it” kind of person. A few reviewers mentioned the included instructions are minimal — they had to watch a YouTube video to figure out the adapter alignment.

Also note: this filter is not a code-approved replacement for a proper vent termination. If your local inspector is strict, you may need to keep the original cap and install the OdorHog as an inline filter lower on the stack. Some buyers do exactly that to avoid roof work entirely.

Who Should Buy This

• Homeowners with persistent sewer gas smells — especially if the odor is worse after rain or wind shifts. This is your diagnostic tool and your fix in one.
• RV and boat owners — the compact size and 2-inch adapter make it perfect for black water tank vents where odor is a constant annoyance.
• DIYers who can cut and glue PVC — if you’ve done a sink drain before, you can handle this install.

Skip It If

• You expect a zero-maintenance, permanent solution. The carbon media will need replacing, and you’ll need to climb back up there to do it.
• You’re renting and can’t modify the roof plumbing.
• Your vent stack is cast iron — the ABS adapters won’t bond to metal without additional work.

FAQ

Q: Will this work on a 1.5-inch vent pipe?
A: No — the smallest adapter is 2 inches. For a 1.5-inch stack, you’d need a reducing bushing, which is not included and may restrict airflow. Not recommended.

Q: Does it restrict vent airflow enough to cause drain gurgling?
A: In my testing and based on buyer reports, no. The carbon bed is engineered with a large surface area and open-cell structure that allows adequate air exchange. One reviewer noted their drains still ran freely after install.

Q: How do I know when the filter is exhausted?
A: You’ll smell it. The odor returns gradually, not suddenly. If you start noticing a faint sewer smell near the vent after several months, it’s time to swap the cartridge. Some buyers mark the install date on the cap with a Sharpie to track it.

The Verdict

Buy it if you’re tired of sewer gas smells and want a proven, mechanical solution that doesn’t rely on masking sprays or “maybe it’s the wind” theories. It’s durable, effective, and the 4-size fit means you’re covered for most standard residential stacks.

Skip it if you’re not prepared for the cutting/gluing install or the recurring cartridge replacement cost. This is a real filter doing real work — it’s not a set-and-forget gadget.

Rating: 4.6/5 — Loses a half-star for the installation friction and the disposable media cost, but for the core job of killing sewer gas odor, it’s the best option I’ve tested.

Where to Buy

👉 Check Price on Amazon →

We earn a small commission at no extra cost to you — this helps fund more honest reviews.

Last updated: 2026-08-06. Ratings and prices current as of review date. Verify on Amazon before purchasing.