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The Rheem 18kW Tankless Electric Water Heater is a solid choice for those looking for an efficient and space-saving solution to hot water needs. Its compact size (14.5"W x 18.25"H) makes it ideal for homes with limited space, and the wall-mount design allows for easy installation. With a maximum flow rate of 4.4 gallons per minute, it can adequately serve smaller households or apartments, meeting the demands for showers and other hot water needs simultaneously.
One of the key strengths of this model is its impressive energy efficiency, boasting a 99.8% efficiency rating. This not only helps reduce energy bills but also makes it an eco-friendly option. The external digital thermostatic control with LED display allows for precise temperature adjustments, which can be a great feature for users who value control over their hot water supply.
There are some considerations to keep in mind. While the recovery rate is decent for its size, larger families might find the output insufficient during peak usage times. Additionally, installation might require a professional, especially if your existing plumbing does not match the specifications. Some customers have also noted that while the unit is generally reliable, it may not handle extremely high volumes of hot water demand as effectively as larger tank systems.
The warranty and customer service provided by Rheem is a plus, offering peace of mind should any issues arise. Safety features are also included, which is essential for households with children. The Rheem 18kW Tankless Electric Water Heater is best suited for smaller homes or apartments focused on energy efficiency and compact design, but larger families may need to consider their hot water demands before making a decision.
The Rheem 8kW 240V Tankless Electric Water Heater is a compact and energy-efficient option for providing on-demand hot water in smaller households or for limited use points like a single bathroom or kitchen sink. Its tankless design means it heats water continuously, so you don’t have to wait for a tank to refill, which helps save space and potentially reduces energy waste compared to traditional tank heaters. The unit has an 8kW power rating and can deliver a flow rate of up to 1.95 gallons per minute, making it suitable for low-to-moderate hot water needs but likely not enough for whole-house use or multiple simultaneous showers.
The adjustable digital temperature display and ON/OFF dial control offer easy temperature customization. At just over 12 inches tall and 8 inches wide, it fits well in tight spaces and mounts on a wall, which is great if installation space is limited. The maximum operating pressure is 150 PSI, which is standard but something to confirm with your home plumbing setup.
Rheem is a reputable brand known for reliable water heaters, which adds confidence in durability. This unit is a practical choice if you need a small, efficient electric water heater for point-of-use applications, though it may not meet the demands of larger households or multiple simultaneous users.
The Westinghouse 24kW tankless water heater is designed for large homes needing a steady flow of hot water without the wait typical of tank heaters. It delivers up to 5.55 gallons per minute, which can comfortably handle two showers and a sink at once, making it a strong fit for busy households. Because it's tankless, it provides endless hot water and saves floor space by mounting directly on the wall with a compact size of about 13 by 17 inches. Energy efficiency is good here, as it heats water on demand rather than keeping a tank hot all day.
The product is equipped with smart WiFi control, allowing you to adjust water temperature precisely and control the unit remotely via an app or voice commands with Alexa or Google Home—this adds convenience especially if you want to manage settings without going near the unit. Safety is well covered with ETL certification and multiple protections against leaks, overheating, and electrical issues, plus an IPX4 rating that guards against water splash. Installation requires a 240V supply and appropriate breakers, which might need professional setup considering the high current involved.
Note that the activation flow is 0.79 gallons per minute, meaning very low water flows might not trigger heating immediately. The unit carries a respectable 4.3 out of 5 rating from users, reflecting reliable performance. For large households looking for a modern, space-saving, and smart-controlled electric water heater, this Westinghouse model offers strong performance alongside good safety features, though installation complexity and electrical requirements might be factors to consider.
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