Rheem 18kW 240V Tankless Electric Water Heater
Experience consistent, endless hot water on demand with the Rheem RTEX-13 Electric Tankless Water Heater. This compact, stylish unit delivers precise temperature control in 1°F increments, ranging from 80°F to 140°F, while maintaining an impressive 99.8% energy efficiency. Designed for quick hot water delivery for single or multiple uses, it features durable copper immersion heating elements with brass tops for longevity. Installation is simplified with included adapters and external controls, making it an excellent, energy-saving upgrade for modern homes needing reliable hot water flow.
$262.00
Owner Satisfaction
4.0
/ 5
Category Rank
174
/ 222
#174 in Water Heaters
Price vs Category Average
-71%
Below average
Power
13
/ KW
Who it's for
- High Energy Efficiency
- Continuous Hot Water Supply
- Compact and Space-Saving Design
Who should skip it
- Significant Electrical Service Demand
- Limited Flow Rate in Cold Climates
- Higher Initial Purchase Price
Key Specs
Power
13KW
Flow Rate
6.0 GPM
Energy Efficiency Rating
99.8%
Temperature Range
80°F to 140°F
Heating Elements
Robust copper immersion with brass top
Dimensions
Height: 6.75 inches, Length: 14 inches, Width: 10.3 inches
Water Connections
Side 1/2" compression
Fuel Type
Electric
Features
- Provides on-demand, endless hot water supply
- Achieves 99.8% energy efficiency rating
- Digital temperature control in 1°F increments
- Compact and stylish design
- Durable copper immersion heating elements
- Simple installation with included adapters
- External controls for easy temperature adjustment
- Suitable for whole-home or point-of-use needs
What customers say
Customers highly value the Rheem 18kW tankless heater for its compact design and reliable, on-demand hot water, noting energy efficiency savings. The core theme revolves around installation complexity and performance limitations. This unit demands significant electrical upgrades, often increasing total cost and requiring professional help. Furthermore, performance is highly dependent on incoming water temperature. Users in colder climates report struggles maintaining high flow rates for multiple fixtures simultaneously. Satisfaction is highest when the unit is correctly sized for warmer climates or point-of-use applications. Success hinges on accurately assessing electrical capacity and understanding climate related output constraints.
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