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Mizudo FDG-CS80 vs Turbro WH-65K: which uses less energy?

At the low draw pattern the Turbro WH-65K uses 93 therms a year and the Mizudo FDG-CS80 95 — 1 therms (1%) less, about 12 therms over ten years. Both are filed as a gas 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 a gas tankless unit at the low draw pattern.

Filed and computed figures
Figure Mizudo FDG-CS80 Turbro WH-65K
UEF (Uniform Energy Factor) 0.81 0.82 (better)
Energy use per year (therms) 95 93 (better)
Max flow (GPM) 2.1 2.4
Installed cost range NLR REMDB $1,698–$2,632 $1,745–$2,687
CPSC recall naming it CPSC none on file none on file

DOE CCD · 2026-09-19 NLR REMDB · 2026-04-01 CPSC · 2026-09-24


What it costs to run

  • Mizudo FDG-CS80 95 therms a year
  • Turbro WH-65K 93 therms a year

Turbro WH-65K is 2 therms a year lower than Mizudo FDG-CS80.

DOE CCD · 2026-09-19

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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 above.
  • No CPSC recall on file names either model (list checked 2026-09-24).
  • The actual warranty term is printed in each model’s documentation, not in any registry.

Which should you pick?

  • Pick the Turbro WH-65K if running cost matters most: it uses 1 therms less a year on the same test.
  • Pick the Mizudo FDG-CS80 if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the Turbro WH-65K.
  • Neither if you need more than 2.4 GPM at the same time — neither unit lists more. Check how to size a tankless unit by GPM.

Each model on its own

  • Mizudo FDG-CS80 Filed figures, class position, running cost on your ZIP 95 therms a year
  • Turbro WH-65K Filed figures, class position, running cost on your ZIP 93 therms a year