What it delivers
The Rheem RTEX-11 Electric Tankless Water Heater is a compact electric tankless rated at 11 kW on 240 volts. Its listing gives a maximum flow of 2.7 GPM.
Expect about 1.1 GPM with cold winter water (a 70°F rise) and 1.7 GPM when the inlet is milder (45°F rise); that is less than one 2 GPM shower in January. Size it to your fixtures.
At 240 volts 11 kW is about 46 amps. The maker calls for one- 50‑amp double‑pole breaker. The requirement calculator shows it at 208 V too; an electrician confirms the panel.
No flue, no gas line and a compact box on the wall; the trade-off is that a cold winter inlet cuts its flow sharply.
Listed details: features: LED Display; material: Stainless Steel; model: RTEX-11; warranty: Limited lifetime warranty.
The listing gives dimensions of 8.25 in (W) x 12.63 in (H), a weight of 3.2 kg and fittings, aerators in the box.
Warranty, per the listing: Limited lifetime warranty.
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
- 11 kW
- Up to 2.7 GPM
- No venting or gas line
- Breakers stated by the maker
Trade-offs
- Winter flow is much lower
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 | RTEX-11 | Retailer |
|---|---|---|
| Dimensions (seller) | 8.25"W x 12.63"H | Retailer |
| Features (seller) | LED Display | Retailer |
| Power | 11 kW | Retailer |
| Voltage | 240 V | Retailer |
| Max flow (maker) | 2.68 GPM | Retailer |
| Product weight | 3.2 kg | Retailer |
| Material | Stainless Steel | Retailer |
| Warranty | Limited lifetime warranty | Retailer |
| Breakers (maker) | one- 50‑amp double‑pole breaker | Retailer |
Rival units at this flow
More electric tankless water heaters rated for similar demand
- WINTEMP WM15V 14.4 kW Electric Tankless Water Heater
- Rheem RTEX-13 Electric Tankless Water Heater
- Stiebel Eltron DHX 10-2 Trend 9.6 kW Electric Tankless Water Heater
- Westinghouse HEU-ET014KA1G-A2 14 kW Electric Tankless Water Heater
Full electric tankless water heaters spec grid · Every Rheem unit in the catalog
Final verdict
A well-specified compact electric tankless for light use in mild climates.
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