Dolphin EON 120d Review (2026): Same Naming Trap as the EON 100, Now With a Bigger Warranty Gap

Quick Answer: The Dolphin EON 120d is Maytronics’ step-up cordless pool cleaner, adding a top-access backwash filter (DebrisLock) over the base EON 100’s fine-filter kit, for pools up to 50 ft. Like the EON 100, it ships under two near-identical SKUs with different warranties: the plain EON 120d (Store Exclusive, no published online price, 3-year warranty) and the Nautilus EON 120d ($1,199 direct from Maytronics, only a 1-year warranty). PCWorld’s hands-on test found the backwash filter traps debris well but is a real chore to clean afterward.

Maytronics introduced the EON cordless family with the EON 100, and the 120d sits one tier up — same core cordless platform, pricier backwash filtration instead of a basic fine-filter kit. Checking Maytronics’ own two product pages for it surfaces the identical naming trap this site already flagged on the EON 100: two SKUs, two warranties, one nearly-identical name.

Dolphin EON 120d at a glance

Want it in hand before the weekend instead of waiting on standard shipping? A free 30-day Amazon Prime trial covers fast delivery — cancel before day 30 if you don’t keep it.

By the numbers

• Warranty gap: 3 years on the plain EON 120d vs 1 year on the Nautilus EON 120d — per Maytronics’ own two product pages. That’s a bigger spread than the EON 100’s 2-year/1-year split, making the warranty the single biggest reason to confirm your exact SKU before buying.
• Runtime claims disagree across Maytronics’ own pages: the plain EON 120d page says “up to 2 weeks,” the Nautilus EON 120d page says “up to 2.5 weeks,” and a separate Maytronics blog post gives a different unit entirely — “up to 4 hours of runtime on a single charge.” PCWorld’s reviewer noted the longest available cycle (3 hours on the unit he tested) “doesn’t make full use of its battery capacity.”
• Filter cleanup, independently tested: PCWorld found the DebrisLock backwash basket traps fine debris and grit effectively, but leaves got stuck between grille layers that hosing couldn’t dislodge — he had to pick dozens out by hand, and called the cleanup process something that “effectively killed my interest in using it regularly.”
• Coverage ceiling matches the cheaper EON 100: both families top out at 50 ft pools and 4,000 GPH suction (where listed) — the 120d’s extra cost buys a different filter, not more cleaning power.

What it does well

Effective fine-debris capture. PCWorld’s hands-on test confirmed the DebrisLock filter traps dirt and grit well, and the robot reached about 95% coverage with synthetic leaves on its longest cycle.

Maneuvers well, including on stairs, per the same independent review — a genuine strength distinct from the filter complaints below.

Longer base warranty than most of the lineup, at least on the plain EON 120d SKU — 3 years beats every other Dolphin cordless model reviewed on this site so far, including the EON 100’s best case of 2 years.

Where it falls short

• Backwash filter cleanup is a real chore. PCWorld’s independently tested unit left leaves wedged between grille layers that hosing wouldn’t clear, forcing hand-removal — and the reviewer said it discouraged regular use entirely.
• Two SKUs, two warranties, one nearly-identical name — exactly the same naming trap this site already flagged on the cheaper EON 100, just with a wider gap (3yr vs 1yr instead of 2yr vs 1yr).
• Maytronics’ own pages don’t agree on runtime — “2 weeks,” “2.5 weeks,” and “4 hours” all appear across different official Maytronics pages for this same product family, with no single authoritative figure.
• Reported startup problems and missed corners in PCWorld’s independent test — the unit failed to start on the reviewer’s first two attempts, and it regularly missed corners during cleaning runs.
• The plain EON 120d has no published online price. Like the EON 100’s equivalent SKU, it’s “Store Exclusive,” so you’d need to contact a local dealer for an actual number.

Dolphin EON 120d vs the alternatives

The 120d’s real upgrade over the EON 100 is the backwash DebrisLock filter rather than a basic fine-filter kit — but PCWorld’s independent test found that upgrade comes with its own cleanup burden, not a clear win. If filter-basket maintenance matters more to you than filtration depth, the cheaper EON 100’s simpler fine-filter kit may actually be the easier cleaner to live with day to day. For the complete current Dolphin lineup, see the best Dolphin pool cleaner guide; for other cordless brands, see our best cordless robotic pool cleaner rankings.

Who should buy the Dolphin EON 120d

Buy it if you specifically want backwash filtration over a basic fine-filter kit, you’re comfortable committing to hand-cleaning a filter basket occasionally, and you’re willing to confirm which exact SKU — plain EON 120d or Nautilus EON 120d — you’re actually ordering before checkout.

Look elsewhere if filter cleanup ease matters more than filtration depth (the cheaper EON 100 may suit you better), or if you want a single consistent runtime figure from the manufacturer — Maytronics’ own pages for this exact product don’t agree with each other.

The bottom line

The Dolphin EON 120d brings backwash filtration to Maytronics’ cordless EON lineup, and PCWorld’s independent test confirms it captures debris well — but cleaning that filter afterward was enough of a chore to turn the reviewer off regular use. Add in the same two-SKU naming trap already seen on the cheaper EON 100 (here a steeper 3-year vs 1-year warranty split) and Maytronics’ own inconsistent runtime claims across its own product pages, and the 120d is a cleaner that rewards confirming every detail — SKU, warranty, and filter-maintenance tolerance — before you buy.