What it delivers
The Ranein RE27K 27 kW Electric Tankless Water Heater is a whole-house electric tankless rated at 27 kW on 240 volts. Its listing gives a maximum flow of 6.5 GPM.
Worked out from its input, it delivers roughly 4.1 GPM when the water only has to rise 45°F, and 2.6 GPM at a 70°F winter rise: 2 showers at 2 GPM in summer, 1 shower at 2 GPM in winter. Size it to your fixtures.
At 240 volts 27 kW is about 112 amps. The maker calls for 3 × 40 A double-pole breakers. The requirement calculator shows it at 208 V too; an electrician confirms the panel.
Electric tankless units need no venting and no gas, and work best where inlet water stays mild, because every degree of rise costs flow.
Other listed details: features: Energy and Space Saving; connections: 3/4" npt; material: Iron; model: RE27K.
The listing gives dimensions of 13.8 in (W) x 18.7 in (H) and a weight of 14.4 lb.
Right unit for this house?
Install it when
- 2 showers at once 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
- 27 kW
- Up to 6.5 GPM
- No venting or gas line
- Breakers stated by the maker
Trade-offs
- Draws about 112 A
- Flow drops with cold inlet water
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 | RE27K | Retailer |
|---|---|---|
| Dimensions (seller) | 13.8"W x 18.7"H | Retailer |
| Features (seller) | Energy and Space Saving | Retailer |
| Power | 27 kW | Retailer |
| Voltage | 240 V | Retailer |
| Product weight | 14.4 lb | Retailer |
| Material | Iron | Retailer |
| Max flow (maker) | 6.5 | Retailer |
| Breakers (maker) | 3 × 40 A double-pole breakers | Retailer |
| Connections | 3/4" npt | Retailer |
Rival units at this flow
More electric tankless water heaters rated for similar demand
- VancEpic RE27K 27 kW Electric Tankless Water Heater
- Westinghouse ET018KA1G 18 kW Electric Tankless Water Heater
- GE GE18SNHPDG 18 kW Electric Tankless Water Heater
- ThermoMate ET270 27 kW Electric Tankless Water Heater
Full electric tankless water heaters spec grid · Every Ranein unit in the catalog
Final verdict
A sensible whole-house electric tankless for 2 showers at once in mild climates.
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