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Friedrich PROPH80 T0 RH120-M vs Lochinvar HPTS-66 2**: which uses less energy?

An asterisk in a model number stands for any character: one filing covers several variants.

At the high draw pattern the Lochinvar HPTS-66 2** uses 1,341 kWh a year and the Friedrich PROPH80 T0 RH120-M 1,434 — 93 kWh (6%) less, about 930 kWh over ten years. Both are filed as an electric tank, 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 tank at the high draw pattern.

Filed and computed figures
Figure Friedrich PROPH80 T0 RH120-M Lochinvar HPTS-66 2**
UEF (Uniform Energy Factor) 3.46 3.7 (better)
Energy use per year (kWh) 1,434 1,341 (better)
First hour rating (gal) 84 82
Rated storage volume (gal) 72 67
Installed cost range NLR REMDB $3,866–$4,365 $3,732–$4,558
ENERGY STAR certified ENERGY STAR yes yes
Refrigerant ENERGY STAR R-134a, GWP 1430 R-134a, GWP 1430
On the market since ENERGY STAR 2024-03-01 2022-06-06
CPSC recall naming it CPSC none on file none on file

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


What it costs to run

  • Friedrich PROPH80 T0 RH120-M 1,434 kWh a year
  • Lochinvar HPTS-66 2** 1,341 kWh a year

Lochinvar HPTS-66 2** is 93 kWh a year lower than Friedrich PROPH80 T0 RH120-M.

DOE CCD · 2026-09-19

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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).
  • Both are ENERGY STAR certified, which requires a manufacturer warranty of at least six years; the actual term for each model is not published.
  • Time on the market, as filed with ENERGY STAR: the Friedrich PROPH80 T0 RH120-M since 2024-03-01, the Lochinvar HPTS-66 2** since 2022-06-06. A sale date, not a lifespan.

Which should you pick?

  • Pick the Lochinvar HPTS-66 2** if running cost matters most: it uses 93 kWh less a year on the same test.
  • Pick the Friedrich PROPH80 T0 RH120-M if you need more hot water in your busiest hour: it lists a first hour rating of 84 gallons against 82.
  • Neither if your household's busiest hour needs more than 84 gallons of hot water — neither lists more. Check whether a 65-gallon heater is enough.

Each model on its own