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Written from the listing and 451 buyer reviews, not from our own use · How we rate
The Stiebel Eltron Tempra 29 Plus keeps it simple: an electric tankless heater with 28.8 kW at 240 V. It made our top 5 whole-house electric tankless water heaters: a great match for a home without gas and with a big panel.
These are sold as variants of one listing family. Each variant has its own page.
| Brand | Stiebel Eltron |
|---|---|
| Category | Electric tankless water heaters |
| Fuel | Electric |
| Stated heating power | 28.8 kW |
| Stated voltage | 240 V |
| Total current | 200 A |
| Buyer reviews | 451 · 4.4/5 |
| ASIN | B07GYQHWYJ |
Full listing title: Stiebel Eltron Tempra 29 Plus Electric Tankless Water Heater, 28.8kW, 240V
| Fuel | ElectricFull listing title |
|---|---|
| Stated heating power | 28.8kWFull listing title |
| Stated voltage | 240VFull listing title |
#3 of 5 in our Whole-House Electric Tankless Heaters ranking
What it's made for: a home without gas and with a big panel.
The two picks next to it in our whole-house electric tankless water heaters ranking, with their rating and a dated price.
The heating power the listing states. At 240 V it draws about 120 A. Before you think about showers, your electrician has to say yes to that number at the panel in the garage.
Warm tap water: where it comes in around 62 °F (much of the South), 28.8 kW gives about 4.6 GPM of 105 °F water on our calculator's maths. That's two 2 GPM showers at once.
A cold January: where it comes in at 42 °F, it's about 3.1 GPM, one 2 GPM shower at a time. Up north, that's the figure to size against, and it's why the honest answer is sometimes a second unit or gas.
What the Stiebel Eltron Tempra 29 Plus listing names:
The installation manual has the last word on breakers and wire size; show it to your electrician before you order.
At the price on Sep 30, 2026, each kW of stated heating power works out at about $27.74 (price ÷ stated kW, our arithmetic). That puts it in the pricier third of the 27 whole-house electric tankless heaters we have a price and a stated power for.
Budget for the electrician as well: new double-pole breakers, thick wire from the panel and, if the panel is full, an upgrade.
The button opens the exact listing (ASIN B07GYQHWYJ), where today's price, stock and seller apply. Sizes and variants of the same family often sit at different prices.
Colder tap water where you live? The WINTEMP WN-36kW Electric, 240V (8.1/10) is rated 36 kW.
Panel short on spare amps? The Rheem 18 kW Electric, 240V (9.3/10) is rated 18 kW, about 75 A at 240 V.
Only one sink far from the heater? The ThermoMate 14 kW Electric, 240V (7.9/10) is a 14 kW point-of-use unit.
Our take
The best thing about the Stiebel Eltron Tempra 29 Plus is 28.8 kW at 240 V. 451 buyers back that up with 4.4/5, about as reassuring as a review record gets. The one thing that bugs us: no stated self-modulation, while most picks here have it. We'd pick it if your house has no gas and a 200 A panel with room to spare; otherwise, put it next to the WINTEMP WN-36kW Electric (240V) first.
New breakers, the unit on the wall next to the old tank's spot, water in and out. An electrician does the panel side.
Hot in a few seconds once the water in the pipes has passed. Set it, then leave it.
With 42 °F water coming in, 28.8 kW gives about 3.1 GPM at 105 °F on our calculator's maths. Low-flow shower heads stretch that further.
Clean the inlet screen and flush out scale on hard water. Our flushing and descaling guide has the routine.
Buyers give it 4.4/5, a strong record, above this ranking's 4.3 average. And with 451 reviews behind it, that number is hard to argue with.
Before the Stiebel Eltron Tempra 29 Plus ships, check your panel: it draws 200 A, so an electrician should look at the panel first.
Take a photo of the panel label (main breaker size and free slots) and send it to the electrician with the listing. Our electrical requirements guide explains what they will look for.
On our calculator's maths, 28.8 kW gives about 3.1 GPM with 42 °F winter water and 4.6 GPM with 62 °F water. Our flow-rate calculator does it for your region.
Hardwired 240 V work needs a licensed electrician and often a permit. Our install cost guide shows what usually ends up on the quote.
Hard water still builds up on the elements and the inlet screen. Our flushing and descaling guide covers the routine.
How the Stiebel Eltron Tempra 29 Plus stacks up against the closest alternative in our ranking, the WINTEMP WN-36kW Electric (240V).
| Criterion | Stiebel Eltron Tempra 29 Plus | WINTEMP WN-36kW Electric, 240V |
|---|---|---|
| Our rating | 7.9/10 | 8.1/10 |
| Heating power | 28.8 kW | 36 kW |
| Max flow | Not stated | 8.7 GPM |
| Self-modulating | Not stated | Stated |
| Warranty | Not stated | 2 years |
| Buyer reviews | 451 · 4.4/5 | 203 · 4.4/5 |
Pick the WINTEMP WN-36kW Electric (240V) if you want our higher-rated option (8.1/10), with more power (36 kW) and more stated flow (8.7 GPM).
We rate it 7.9/10 (very good), #3 of 5 in our whole-house electric tankless water heater ranking. It is based on 451 buyer reviews averaging 4.4/5 and the specifications stated in the listing.
The listing states a heating power of 28.8 kW on 240 V. The headline flow is a mild-weather number: with cold winter water coming in, the same unit gives you less. Read the maker's flow chart at your winter rise, or let our flow-rate calculator do the sums.
The listing states 240 V and 28.8 kW. At 240 V, that is roughly 120 A. A licensed electrician checks the panel, the breakers and the wiring before it goes on the wall.
Its listing states 28.8 kW of heating power. These are the seller's figures, not our measurements: how steady the temperature is in your shower and how it copes with your winter water can't be read from a listing.
Your panel: take a photo of the panel label (main breaker size and free slots) and send it to the electrician with the listing. Our electrical requirements guide explains what they will look for. Your winter flow: on our calculator's maths, 28.8 kW gives about 3.1 GPM with 42 °F winter water and 4.6 GPM with 62 °F water. Our flow-rate calculator does it for your region. The install: hardwired 240 V work needs a licensed electrician and often a permit. Our install cost guide shows what usually ends up on the quote. Scale: hard water still builds up on the elements and the inlet screen. Our flushing and descaling guide covers the routine.
We link to the exact listing on Amazon, where today's price, stock and seller apply. It is an affiliate link, and it has no effect on the rating.
No, we haven't used it ourselves. Everything on this page comes from its listing and 451 buyer reviews, read line by line and weighed with our published formula.
If the Stiebel Eltron Tempra 29 Plus hasn't sold you yet, see where it ranks, read the guides that feature it or browse all electric tankless water heaters.