DoesTheMath

EEMAX ECO 11 vs Mizudo ET011: which uses less energy?

At the very small draw pattern the Mizudo ET011 uses 628 kWh a year and the EEMAX ECO 11 642 — 14 kWh (2%) less, about 137 kWh over ten years. Both are filed as an electric tankless unit, so the comparison holds. Enter your ZIP below to price the difference.


Side by side

Compared within one class only: models filed as an electric tankless unit at the very small draw pattern.

Filed and computed figures
Figure EEMAX ECO 11 Mizudo ET011
UEF (Uniform Energy Factor) 0.92 0.94 (better)
Energy use per year (kWh) 642 628 (better)
Max flow (GPM) 1.2 1.2
Installed cost range $1,294–$1,742 $1,300–$1,790
ENERGY STAR certified not matched not matched
DOE CCD · 2026-09-19

What it costs to run

EEMAX ECO 11: 642 kWh a year Mizudo ET011: 628 kWh a year

EEMAX ECO 11 — 642 kWh a year Mizudo ET011 — 628 kWh a year

Mizudo ET011 is 14 kWh a year lower than EEMAX ECO 11.

DOE CCD · 2026-09-19

Report an issue with this number

Enter your ZIP to price both units on the same rate where you live.


Reliability

Not published: Reliability, failure rates and each model’s actual warranty term.

The registries these figures come from certify energy performance under a federal test; none of them records how long a unit lasts or how often it fails, so this page does not rank the two on reliability.

What is here instead:

  • The filed efficiency, capacity and tank size of both models, side by side below.
  • The actual warranty term is printed in each model’s documentation, not in any registry.

Which should you pick?

  • Pick the Mizudo ET011 if running cost matters most: it uses 14 kWh less a year on the same test.
  • Pick the EEMAX ECO 11 if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the Mizudo ET011.
  • Neither if you need more than 1.2 GPM at the same time — neither unit lists more. Check how to size a tankless unit by GPM.

Each model on its own