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Rheem RTEX-18 Tankless Water Heater
Rheem RTEX-18 is one of the most popular models of Rheem. The RTEX-18 is equipped with a brass heat exchanger and rugged copper built to withstand harsh water conditions. This tankless water heater has 2 heating chambers with 18kW full power.
The Rheem RTEX-18 has a unique and simple design. It is a slim and lightweight water heater that ensures longevity, compactness, and usability to its best. Working in ideal conditions, the hot water flow can reach 4.4 GPM which is best for small and medium households.
The installation process is also quite simple, you can install it at any nook and corner of your house due to its space-saving design. Another installing convenience is its 240V standard voltage which every electrician values. RTEX-18 has very low energy consumption as it runs only when needed.
There is an on-unit control system for easy temperature adjustments. It has considerable low amperage of 75 A which struck a great balance between electric heater without an electric grid update. It can easily cover two bathrooms in hot and cold weather.
It is a solid choice for homes, condos, apartments, hospitals, boats, offices, hotels, and restaurants. Among other things, Rheem RTEX-18 is a highly powerful and eco-friendly water heater because of its low profile design.
Quick Features
- Digital thermostatic control with LED display.
- Brass/copper heat exchanger
- 4 GPM flow rate.
- Ideal for small and medium house owners.
- Simple and easy installation.
- Most advanced self-modulation.
- Robust copper immersion heating elements.
- Energy-efficient water heater.
- 10-years heat exchanger warranty
Pros
- Low amperage of 75 A.
- Very affordable and reliable heater.
- Easy to install and use.
- Stylish and compact
- Can fit virtually anywhere.
- On-unit controlling feature
Cons
- Not recommended for big households.

Hi, This is Luis. Author at “TheHeatersGuide”. I am a graduate in Mechanical Engineering. Currently researching on heating technology. However, I have learned many home heating techniques and still learning the home heating technolgy. And I love to share my research and reviews.