FRIEDRICH PROG50S-40N RH61 vs Rheem PROG48-48U RH EC1: which uses less energy?
At the high draw pattern the Rheem PROG48-48U RH EC1 uses 264 therms a year and the FRIEDRICH PROG50S-40N RH61 269 — 4 therms (2%) less, about 42 therms over ten years. Both are filed as a gas tank, 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 tank at the high draw pattern.
| Figure | FRIEDRICH PROG50S-40N RH61 | Rheem PROG48-48U RH EC1 |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.63 | 0.64 (better) |
| Energy use per year (therms) | 269 | 264 (better) |
| First hour rating (gal) | 87 | 88 |
| Rated storage volume (gal) | 48 | 46 |
| Installed cost range | $1,732–$2,981 | $1,761–$3,058 |
| ENERGY STAR certified | not matched | not matched |
What it costs to run
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 Rheem PROG48-48U RH EC1 if running cost matters most: it uses 4 therms less a year on the same test.
- Pick the FRIEDRICH PROG50S-40N RH61 if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the Rheem PROG48-48U RH EC1.
- Neither if your household's busiest hour needs more than 88 gallons of hot water — neither lists more. Check whether a 50-gallon heater is enough.
Each model on its own
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FRIEDRICH PROG50S-40N RH61
Its filed figures, class position and running cost on your ZIP.
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Rheem PROG48-48U RH EC1
Its filed figures, class position and running cost on your ZIP.