HEAT-FLO SSL-20S vs Stiebel Eltron PSH 20: which uses less energy?
At the low draw pattern the Stiebel Eltron PSH 20 uses 2,413 kWh a year and the HEAT-FLO SSL-20S 2,439 — 26 kWh (1%) less, about 262 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 low draw pattern.
| Figure | HEAT-FLO SSL-20S | Stiebel Eltron PSH 20 |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.92 | 0.93 (better) |
| Energy use per year (kWh) | 2,439 | 2,413 (better) |
| First hour rating (gal) | 33 | 30 |
| Rated storage volume (gal) | 23 | 21 |
| Installed cost range | not published | not published |
| 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 Stiebel Eltron PSH 20 if running cost matters most: it uses 26 kWh less a year on the same test.
- Pick the HEAT-FLO SSL-20S if you need more hot water in your busiest hour: it lists a first hour rating of 33 gallons against 30.
- Neither if your household's busiest hour needs more than 33 gallons of hot water — neither lists more.
Each model on its own
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HEAT-FLO SSL-20S
Its filed figures, class position and running cost on your ZIP.
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Stiebel Eltron PSH 20
Its filed figures, class position and running cost on your ZIP.