Charlotte Pipe 4" Repair Coupling Pipe Fitting - Schedule 40 ABS DWV (Drain, Waste and Vent) Durable, Easy to Install, High Tensile and Sound Deadening for Home or Industrial Use

Why I reached for this coupling

Midway through replacing a cracked section of a 4-inch DWV stack, I needed a fast, permanent way to bridge a gap without tearing apart more of the system than necessary. I grabbed the 4-inch ABS repair coupling from Charlotte Pipe because it’s made for exactly this kind of non-pressurized drain, waste, and vent work, and because ABS solvent welding is straightforward: no primer, quick set, strong bond. I’ve used rubber couplers with clamps in the past when I needed serviceability, but this time I wanted a rigid, code-friendly fix that wouldn’t wiggle over time. This coupling did the job cleanly.

What it is and what it’s for

This is a Schedule 40 ABS repair coupling designed for DWV and sewer/storm drainage systems. It’s foam-core ABS, which keeps the weight down and does a decent job of dampening pipe noise compared to some solid-wall plastics or metal. It’s not for pressure lines, and you shouldn’t use or test it with compressed air or gas. It’s rated up to 140°F, which covers typical residential drains, vents, and most appliance discharges once diluted in the line. It conforms to NSF Standard 14 and, being ABS, installs with solvent cement—no primer required.

As a “repair” coupling, it doesn’t have an internal center stop. That makes it possible to slide the coupling fully onto one pipe, align your new segment, then slide it back over the joint to bridge the gap—hugely useful when you can’t flex the system to fit a standard hubbed coupling.

Fit, finish, and build

The coupling I used was dimensionally consistent, with clean, square faces and smooth bores. The ID tolerance felt right—tight enough to grab with solvent cement but not so snug that you’re fighting it in the field. The foam-core wall is lighter than solid ABS, which is good overhead or in awkward spaces. The exterior is a typical matte black ABS finish that takes a marker well for depth marking.

Because it’s foam-core, I treat it like any other DWV-only component: strong in its intended application, but not something I’d rely on for mechanical abuse or any form of pressure. For noise, it helps a bit on vertical runs; it won’t make a thundering stack whisper-quiet on its own, but I do notice less ringing than with thin-wall alternatives.

Installation: quick, but measure twice

The repair went like this:

• I cut out the damaged section with a fine-tooth saw, then deburred and beveled the pipe ends. ABS loves a clean, square cut for maximum bonding area.
• I dry-fit the replacement piece and marked insertion depths on the pipe with a sharpie. With a repair coupling, you’re your own center-stop—those marks matter.
• I slid the coupling fully onto one existing pipe, then set the new segment with a standard hub fitting on the other side.
• Using ABS solvent cement, I buttered the inside of the coupling and the pipe spigot end, made the first joint with a quarter-turn twist, held it for 20–30 seconds, then slid the coupling back over the new joint and repeated.
• After wiping the squeeze-out, I let it set. At room temperature, ABS cement typically gives you handling strength in minutes and solid strength in a couple of hours, but I still avoid load or testing until it’s had a conservative cure window.

No primer means fewer steps and less mess than PVC. The trade-off is that you only get one shot per joint—ABS cement chemically softens and fuses the plastic, and the open time is short. Dry-fitting and marking depth lines make a huge difference in getting a perfect result.

Performance after the fix

Once cured, the assembly felt rigid with no perceptible play at the coupling. I ran a water test (never air) and checked for weeping—bone dry. The joint blended visually with the rest of the ABS stack, and since it’s solvent-welded, there are no clamps to retighten or sleeves to align later. A few months on, it’s still quiet and solid, with zero signs of creep or staining.

Where this coupling shines

• Tight spaces and immovable runs: The no-stop design is ideal when you can’t back a pipe out to make room for a traditional coupling. Slide it on, slide it back, done.
• Permanent, rigid repairs: If you want a “set it and forget it” DWV joint, solvent-welded ABS is tough to beat.
• Speed and simplicity: No primer, no special tools. A basic saw, deburring tool or utility knife, solvent cement, and a rag are plenty.
• Noise characteristics: Foam-core ABS offers a bit of sound deadening compared to some alternatives. In multi-story stacks, every little bit counts.

Limitations to respect

• Non-pressure only: This is not a supply-side fitting and not for compressed air or gas. Use water for any tests.
• Temperature ceiling: Rated to 140°F. Boiling discharges can exceed that at the source; in real-world drains it cools quickly, but I avoid direct connections where sustained higher temps are likely.
• UV exposure: Like most ABS, long-term outdoor sun exposure isn’t ideal. If the vent above the roofline is exposed, paint it with a UV-rated coating per code and manufacturer guidance.
• Code and transitions: Local codes vary on ABS vs. PVC use. If you’re transitioning between the two, you need a listed transition cement or a shielded mechanical coupling—don’t try to fuse ABS to PVC with standard ABS cement.
• Precision required: Without a center stop, it’s on you to measure and mark accurately. Rushing this step can lead to a misaligned or shallow insertion.

ABS repair coupling vs. rubber coupling

Both have a place. A shielded rubber coupling (with a metal band) is great for joining dissimilar materials, handling slight misalignment, or preserving a future point of disassembly. But it remains a mechanical joint that can shift under load if not properly supported. The ABS repair coupling is more compact and eliminates the potential for clamp loosening or sleeve creep. In a concealed location where permanent, code-compliant, like-for-like ABS repair is appropriate, I prefer the solvent-welded option.

Value and availability

This coupling isn’t exotic, but I do favor brand-name fittings for consistency—especially on repairs where tolerances matter. Being made in the USA and listed to NSF Standard 14 are table stakes for me on anything going in a wall or slab. You can find cheaper couplings, but bargain-bin ABS sometimes varies slightly in fit. On a repair that saves hours of labor and prevents a callback, I’ll take the predictable option.

Tips for best results

• Dry fit and mark insertion depths on both sides. A bold line gives you a visual stop so you don’t under-seat the joint.
• Bevel the pipe edges slightly. It reduces the chance of scraping cement off as you insert and helps the pipe center itself.
• Work quickly and support the joint. ABS cement grabs fast; hold your alignment for 20–30 seconds.
• Mind the environment. Cold temps extend set time; in heat, the cement flashes off quicker. Adjust your pace accordingly.
• Use proper support and hangers. A rigid joint still needs proper load distribution to avoid stress at the coupling.

The bottom line

The 4-inch ABS repair coupling from Charlotte Pipe is a straightforward, reliable solution for permanent DWV repairs where you can’t spread the system to insert a standard stopped coupling. It installs fast, bonds strong with standard ABS cement, and the foam-core construction keeps weight down while adding a modest sound-deadening benefit. Respect its limits—non-pressure use only, 140°F rating, and careful measurement—and it rewards you with a clean, rigid joint that disappears into the system.

Recommendation: I recommend this coupling for anyone doing 4-inch ABS DWV repairs who wants a permanent, solvent-welded solution. It’s particularly useful in tight spots and for restoring the rigidity of a stack without resorting to bulky mechanical sleeves. If you need a reversible connection or you’re transitioning materials, a shielded rubber coupling might be a better choice. But for like-for-like ABS in a non-pressurized drain or vent, this repair coupling is the right tool for a clean, durable fix.