Waterdrop 10UA Under Sink Water Filter System, Reduces PFAS, PFOA/PFOS, Lead, Chlorine, Bad Taste & Odor, Under Counter Water Filter Direct Connect to Kitchen Faucet, NSF/ANSI 42 Certified, 1 Year

I installed the Waterdrop 10UA under my kitchen sink on a Saturday morning, and by lunch I’d essentially forgotten it was there—until I poured a glass of cold water. The chlorine bite was gone, the musty notes disappeared, and the water tasted cleaner without that “stripped” flatness I associate with reverse osmosis. For a compact, direct‑connect under‑sink filter at this price, the 10UA punches well above its weight.

Setup and installation

This is one of the simplest under‑sink installs I’ve done. The 10UA uses push‑to‑connect fittings and a twist‑and‑lock cartridge, and it ties directly into standard 3/8-inch U.S. cold‑water lines (a 3/8"-to‑1/2" adapter is included). My process looked like this:

• Shut off the cold water and relieve pressure at the faucet.
• Mount the bracket to the cabinet wall (two screws). If you’d rather avoid drilling in a rental, an industrial Velcro strip works as well, provided the surface is clean and flat.
• Cut the cold‑water feed line and insert the in/out hoses with the included fittings. Seat the push‑to‑connects fully; give them a firm tug to confirm.
• Twist the cartridge onto the head and turn the water back on.
• Flush for five minutes.

No special tools were required beyond a drill/driver and an adjustable wrench. Importantly, this is a cold‑water‑only system, so make sure you’re teeing into the cold line. I didn’t need plumber’s tape on the compression-style fittings; if you end up using any NPT adapters in a custom setup, tape or paste may be appropriate—follow the markings and the manual.

Waterdrop includes a small battery‑powered reminder timer. Stick it inside the cabinet and set it to your preferred service interval so you don’t forget the annual changeout.

Filtration performance

The core of the 10UA is a coconut‑shell activated carbon block with a notably large filtration area, which helps with both adsorption capacity and resistance to clogging. In day‑to‑day use on municipal water, I noticed three tangible improvements:

1) Chlorine reduction and odor removal. The water lost the pool smell and tasted cleaner within minutes of flushing.

2) Clarity and “finish.” Tea and coffee tasted brighter, and ice lost the lingering off‑flavor I’d learned to ignore.

3) Stability over time. After months of use, I haven’t experienced the “early slowdown” some compact filters suffer from. The enlarged surface area appears to be doing its job in keeping pressure drop in check.

The 10UA carries an NSF/ANSI 42 certification, which covers aesthetic reductions like chlorine, taste, and odor. Waterdrop also states reductions for lead and PFAS (including PFOA/PFOS). That said, if your primary concern is verifiable reduction of health‑related contaminants, look for certifications under NSF/ANSI 53/401 specific to those contaminants. For typical city water with chlorine and nuisance tastes, the 10UA is a clear upgrade.

One quirk: after the faucet sits unused for a while, the first second or two can have a faint chlorine note on my setup. A quick two‑to‑five‑second flush resolves it. That’s common with carbon filters as water stagnates in the line, and it’s minor.

A quick note on TDS: this is not a demineralizing system. It retains dissolved minerals like calcium and magnesium, so a TDS meter won’t show a big drop. That’s by design and why the water maintains a natural taste versus the ultra‑low TDS profile of RO.

Flow and day‑to‑day use

There’s a modest reduction in cold‑side flow once the filter is in line—on my faucet it’s around 10–15%. It’s still more than adequate for filling pots, bottles, and the kettle, and I prefer having filtered water through the main faucet rather than adding a separate dispenser. If you already have marginal water pressure, consider a dedicated drinking faucet or routing only the cold side to filtration.

Noise is nil. The system is silent, and because there’s no storage tank or pump, there’s nothing to maintain beyond the cartridge.

Compatibility and upgrades

The 10UA’s direct‑connect design is a strength for apartments, offices, and RVs where you may not want to drill a countertop for a separate spout. It’s compact and tucks neatly against a cabinet wall, leaving room for cleaning supplies. The included adapter handles both 3/8" and 1/2" connections.

Waterdrop offers drop‑in cartridge options if you want to tailor performance. You can upgrade to UF or MZ variants for different filtration goals without replacing the head. If you think you’ll move to a longer or larger cartridge later, mount the head high enough to give yourself vertical clearance.

Maintenance and costs

Service life is rated up to about a year on municipal water (roughly 30,000 liters, depending on water quality and usage). I set the reminder timer to 12 months and plan to change proactively; carbon filters are inexpensive insurance. Replacements are attractively priced compared with many competitors, which makes staying on schedule painless.

A few practical maintenance tips from my experience:

• Flush the filter thoroughly after installation and after any cartridge change.
• If you’re leaving home for more than a couple of weeks, shut off the cold‑water supply to the faucet. Waterdrop notes you can bag and refrigerate the cartridge for up to 30 days if you’ll be away; if in doubt, replace on return.
• Because the carbon is coconut‑shell based, be mindful if you have related allergies (rare, but worth noting).

I’ve had no leaks, but push‑to‑connect fittings require proper insertion. If you can pull the tube out easily, it wasn’t fully seated—remove, trim the end square, and reinsert until it bottoms out.

What I’d change

• Clearer third‑party testing for health‑claim contaminants would inspire more confidence for users with lead or PFAS concerns. The 42 certification is solid for taste and chlorine; adding 53/401 listings would round this out.
• An optional flow‑through bypass or quick shutoff at the head would make cartridge changes even cleaner in tight spaces.
• Including a short guide that demystifies compression vs. NPT fittings and when not to use tape would help first‑time installers.

None of these are deal‑breakers, but they’re areas where a good product could be even better.

Who it’s for

• Households on municipal water who want better‑tasting, cleaner‑smelling water without a countertop pitcher or faucet‑mounted bulk.
• Renters and small spaces where drilling a countertop or adding a tanked RO system isn’t practical.
• RV or office users who need a lightweight, direct‑connect option that doesn’t hinder cabinet storage or require frequent maintenance.

If you’re battling known high lead levels, microbial contamination, or want near‑zero TDS water, a certified lead‑reduction filter, UV treatment, or RO system may be more appropriate.

Recommendation

I recommend the Waterdrop 10UA for anyone on city water who wants a simple, affordable way to remove chlorine and nuisance tastes/odors at the tap while keeping beneficial minerals. It installs quickly, takes up little space, and the annual maintenance cost is low. Taste improved immediately in my kitchen, and the modest flow reduction was a fair tradeoff for better everyday water and better‑tasting tea and coffee. If PFAS or lead is your primary worry, verify certifications for those contaminants or consider stepping up to a system with NSF/ANSI 53/401 listings. For most households seeking a reliable, set‑and‑forget under‑sink filter, the 10UA is an easy, worthwhile upgrade.