240 Volt Rheem RTEX-18 Tankless Water Heater 4.4 GPM
Those looking for a reliable tankless water heater that provides an endless supply of hot water on demand should look no further than the Rheem RTEX-18. Designed for multiple applications or single point of use, this appliance contains highly efficient technology that lets it achieve up to 99.8% energy efficiency, a number that’s hard to match by competitors.
Those looking for a reliable tankless water heater that provides an endless supply of hot water on demand should look no further than the Rheem RTEX-18. Designed for multiple applications or single point of use, this appliance contains highly efficient technology that lets it achieve up to 99.8% energy efficiency, a number that’s hard to match by competitors. Rheem is known to manufacture robust and innovative appliances, especially tankless water heaters that are owned by users across the world. At TopTenWater.com, we’ve researched this appliance to assess how it performs in various conditions and situations.
To begin with, what impressed us was the construction of its immersion heating elements, which are made from copper. This increases durability and allows for easy replacement since they are threaded. Installation is simple with this unit and a digital temperature display allows users to easily see or adjust temperature settings. Since the unit is stylish and compact, it can be installed without sticking out like a sore thumb. Users can change temperature settings in increments of 1 degree and the range lies between 80F degrees to 140F degrees.
As far as specific applications are concerned, the Rheem RTEX-18 tankless water heater can provide 0.5 GPM for a standard bathroom sink, 1 to 1.5 GPM for a kitchen sink, 1 to 1.5 GPM for a washing machine, 1.5 GPM to a water efficient showerhead, 4 GPM to a bathtub, and 2 GPM to a regular showerhead. The max flow on this unit is 4.4 Gallons Per Minute. With advanced self-modulation, users can adjust the power to meet their hot water requirements. Overall, this unit is popular for average applications. Keep reading our analysis at TopTenWater.com for more details.
- This unit comes with an ON/OFF dial control, along with adjustable digital temperature display
- Self-modulating technology allows the unit to be highly efficient
- This unit should not be installed in places where the temperature can drop below freezing
- At least 12 inches of clearance space is suggested above and below the heater
- At least 6 inches of space should be left in front and on the sides of the tankless water heater
|Lower power consumption||Only good for smaller applications|
|Small size ideal to install||Max temperature range 140F degrees|
|Highly affordable||1 GPM output for most applications|
|Highly efficient||Wiring may be complicated for novice users|
- Comes with LED digital thermostat control (external)
- Thermostat has +/-1 degree accuracy
- Adjusts power according to hot water requirements
- Advanced self-modulation technology
- Uses ¾” NPT water connection at bottom
- Simple installation, easy replacement thanks to threaded feature
|Max Temperature||140F degrees|
|Min Temperature||80F degrees|
|Heat Exchanger Warranty||5 years|
|Minimum Activation Rate||0.25 GPM|
|Voltage Connection Required||240V|
|Max BTU||18,000 BTUs|
TopTenWater.com is the preferred destination on the web for people to go to when they’re looking for unbiased content on tankless water heaters. We’ve built a reliable reputation in this niche because our team performs extensive research on each water heater before posting content on it. We’ve done the same for the Rheem RTEX-18 tankless water heater. From Amazon to Home Depot, the team here has delved deep into what customers are saying about the product. Below, we’ve included the highs and lows various users commented on when using the Rheem RTEX-18.
First and foremost, the majority of reviewers have noticed a significant drop in their electric bill after installing the Rheem RTEX-18. Also, these people are happy about having hot water on demand and can use it whenever they want. Another user commented about how silent the unit was since it operated on electricity instead of gas or propane. This means no clicking sounds and no safety risk of using natural gas. Most users said the GPM output of this appliance was fantastic, and whether they used it for showering purposes or doing the dishes, the appliance worked wonderfully
One user was pleased with the durability of this product, however, they weren’t ecstatic about the changes that had to be made to their water system when switching from a tank water heater to a tankless one. They had trouble with the wiring setup since older water heaters require more amperage from the breaker box. A different user complained about Rheem not replacing defective units without receive an OHM reading, which apparently can cost up to $150 where the reviewer lived.
The first reviewer was happy about how much space they were able to save after the purchase and installation of the Rheem RTEX-18 tankless water heater. Another individual stated the product worked great for residential applications and even though their incoming water was very cold, the Rheem tankless water heater did a great job at providing hot water. This user set the temperature to 115F degrees and said this was perfect for their household needs. Most reviewers were happy with the build quality of this unit.
The majority of negative reviews on this appliance had to do with the drastic wiring changes required to run it. Since most people were typically switching from a traditional water heater to this tankless water heater, they had to get professional help to redo the wiring. Without proper installation, the unit did not work. Some users recommended others to only install the unit if they were moving into a newly constructed house.