Quick Answer: The Navien NPE-240A2 and Rheem IKONIC (ECOHS200iN) are both 199,000+ BTU condensing flagships, but they’re built around different priorities — Navien bundles a ComfortFlow recirculation pump and buffer tank standard, while Rheem counters with a small efficiency edge (0.96 vs 0.95 UEF), standard LeakGuard leak detection, and a meaningfully lower price ($1,799 list, recently $1,439 on sale, versus Navien’s $1,884-2,189 street). Buy Navien if built-in recirculation is worth paying more for; buy Rheem if price and leak protection matter more, or if you might need an electric unit down the road.

Navien and Rheem are two of the three condensing gas tankless brands homeowners cross-shop most (the third being Rinnai), and each ships a genuinely different standard feature set rather than competing purely on spec sheet numbers.

FactorNavien (NPE-240A2)Rheem (IKONIC ECOHS200iN)
Max flow (warm inlet)11.2 GPM11.2 GPM
Efficiency (UEF)0.950.96
Heat-exchanger warranty15 years (5 years if uncontrolled recirc)12 years flat
Built-in recirculationYes — ComfortFlow pump + buffer tank standardNo — separate pro RECTGH-SR11iN required
Leak detectionNot standardStandard — LeakGuard Plus
Street price~$1,884-2,189$1,799 list (~$1,439 recent sale)
Electric tankless lineupNoneFull lineup (RTEX/RETEX, 13-36 kW)

By the numbers

Flagship vs flagship: NPE-240A2 vs IKONIC

The Navien NPE-240A2 and Rheem IKONIC ECOHS200iN are both condensing units in the same GPM class — 11.2 warm-inlet peak flow apiece, functionally identical on raw output. Rheem edges ahead on efficiency (0.96 vs 0.95 UEF) and ships EcoNet WiFi with LeakGuard Plus leak detection standard — something Navien doesn’t build into the NPE-240A2. Navien answers with EZNav’s built-in WiFi control panel and a documented 32-unit cascade ceiling (12 common-vented) for larger installs.

The real differentiator: recirculation, out of the box

This is where the two brands genuinely diverge. Navien’s ComfortFlow system pairs a built-in pump with a small onboard buffer tank on the base NPE-240A2 — no second model to buy. Rheem keeps recirculation as a separate purchase: getting the equivalent feature means stepping up to the pro-channel RECTGH-SR11iN instead of the retail IKONIC. If instant hot water at every fixture matters more than price, that bundled pump is Navien’s strongest argument.

Price and leak protection tip the scale toward Rheem

Where Navien wins on recirculation, Rheem wins on cost and safety features. The IKONIC’s $1,799 list price already undercuts Navien’s $1,884-2,189 street price, and Home Depot’s recent $1,439 sale widens that gap to $400-750. Rheem also builds LeakGuard Plus leak detection into the IKONIC standard — it monitors flow patterns and can shut the unit down before a slow leak becomes water damage, a feature you’d need to add separately with Navien.

The deciding factor: do you need electric?

If gas isn’t an option — no line to the house, or you’re outfitting an ADU or apartment — Navien isn’t in the running at all. Navien’s tankless catalog is gas only, while Rheem also makes a full electric tankless lineup, from the point-of-use 13 kW RTEX-13 up to the whole-home 36 kW RTEX-36. That flexibility is one more reason Rheem is often the safer default pick between the two.

Which should you buy?

The bottom line

Navien and Rheem’s flagships are close on raw flow and reasonably close on efficiency, but they’re built around different priorities: Navien bundles recirculation in from the factory, Rheem bundles leak protection and a lower price. Neither is the wrong buy — pick Navien if instant hot water everywhere is worth paying more for, and pick Rheem if you’d rather save money now and add recirculation later (or need an electric unit somewhere down the line). Size whichever you choose to your household’s peak GPM and winter inlet temperature first — see our sizing guide — and confirm venting requirements in our venting guide before you buy.

Rheem IKONIC Super High Efficiency Condensing Gas Tankless (ECOHS200iN)

Best price and leak protection · 199,900 BTU · 11.2 GPM warm inlet · 0.96 UEF · EcoNet WiFi + LeakGuard · $1,799 list ($1,439 recent sale)
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