Head-to-head · Best Tankless Water Heaters

EcoSmart ECO 27 vs Rheem RTEX-24

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

The short answer

Rheem RTEX-24 comes out ahead by a narrow margin (4.6 vs 4.7). The gap is mostly about northern US homes with cold groundwater inlet — read the strengths below before deciding.

Ranked #3 in Best Tankless Water Heaters

EcoSmart ECO 27

4.6

$540

The ECO 27 is the high-flow pick — EcoSmart's best GPM-to-price ratio for households with multiple simultaneous hot-water demands.

Strengths

— 6.6 GPM max — highest in this lineup
— Compact unit saves install space
— 0.3 GPM minimum activation

Watch-outs

— Requires 240V triple-pole breaker
— Some undersizing complaints below 40°F inlet
— Customer support response variable

$540 · Check Price on Amazon Full review →

Higher ratedRanked #2 in Best Tankless Water Heaters

Rheem RTEX-24

4.7

$485

The RTEX-24 is the cold-climate pick — Rheem's flagship that handles northern winter inlet temps better than competitors.

Strengths

— 3,900+ reviews proving reliability
— Excels in cold-inlet conditions (northern climates)
— Self-modulating heating elements

Watch-outs

— Slightly louder than Tempra under load
— No advanced flow control
— Smaller display

$485 · Check Price on Amazon Full review →

How they stack up

EcoSmart ECO 27

Highest GPM. Lifetime element warranty. Undersizes in deep cold.

Rheem RTEX-24

Best for cold climates. Most user reviews. Cheaper than Tempra.

Specs side-by-side

Spec	EcoSmart ECO 27	Rheem RTEX-24
Type	Electric whole-home	Electric whole-home
Power	27 kW	24 kW
Max GPM	6.6	—
Warranty	Lifetime elements	—
Self-Modulating	—	Yes
Reviews	—	3,900+

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