What it delivers
The Stiebel Eltron Tempra 12 Plus 12 kW Electric Tankless Water Heater is a compact electric tankless rated at 12 kW on 240 volts. Its listing gives a maximum flow of 3.0 GPM.
Worked out from its input, it delivers roughly 1.8 GPM when the water only has to rise 45°F, and 1.2 GPM at a 70°F winter rise: less than one 2 GPM shower in summer, less than one 2 GPM shower in winter. Try your own inlet temperature.
At 240 volts 12 kW is about 50 amps. The requirement calculator shows it at 208 V too; an electrician confirms the panel.
It skips venting entirely, but the amps are the hurdle: check the panel before the plumbing.
Other listed details: features: LED Display; material: Copper; model: Tempra 12 Plus.
The listing gives dimensions of 16.63 in (W) x 14.5 in (H) and a weight of 13.5 lb.
Right unit for this house?
Install it when
- Light use in mild climates
- Homes with no gas service
Look at another unit when
- Panels without spare capacity
- More than 1 shower at once in cold winters
Strengths and trade-offs
Strengths
- 12 kW
- Up to 3.0 GPM
- No venting or gas line
Trade-offs
- Flow drops with cold inlet water
- Breaker needs not stated
Install limits
- Figures are the maker's or seller's own. Flow at a rise is our estimate from the input; gas, venting and electrical work needs a licensed professional.
Rated performance
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Model number | Tempra 12 Plus | Retailer |
|---|---|---|
| Dimensions (seller) | 16.63"W x 14.5"H | Retailer |
| Features (seller) | LED Display | Retailer |
| Power | 12 kW | Retailer |
| Voltage | 240 V | Retailer |
| Max flow (maker) | 3 GPM | Retailer |
| Product weight | 13.5 lb | Retailer |
| Material | Copper | Retailer |
Rival units at this flow
More electric tankless water heaters rated for similar demand
- Eemax EX160TC 16 kW Electric Tankless Water Heater
- Eemax EX1608T2 EE 16.6 kW Electric Tankless Water Heater
- Eemax PR013240 13 kW Electric Tankless Water Heater
- Rheem RTEX-36 Electric Tankless Water Heater
Full electric tankless water heaters spec grid · Every Stiebel Eltron unit in the catalog
Final verdict
A sensible compact electric tankless for light use in mild climates.
Buy this unit
Our links open this exact model's product page. Prices and stock change; check what's included before you order.
Each button opens this exact model. We may earn a commission on tracked links; it never changes what we publish. Disclosure