The Rheem RTEX 13 is a compact electric tankless water heater. It weighs 8.5 pounds and is 8.25 inches wide and 12.625 inches tall. The RTEX 13 is a metal box that is compact enough that you can install it under a cabinet or sink in a home, office, boat or RV. On both sides, there are 0.5-inch connections piping water into the unit and moving hot water out of it. You can control temperature from a panel built into the front of the unit. The heater also has a thermostat dial that adjusts temperature over nine settings. Included in the box is a 3-foot electric power cable.
You can use this Rheem tankless water heater for residential or industrial applications. While it can heat water for a small apartment or double-occupant housing unit, it is best suited as a point-of-use water heater. You should only install it to cover a maximum of three fixtures that are not far from the heater. As a single point-of-use heater, the RTEX 13 can serve a garage, shop, laboratory, boat or RV.
The heater only requires 0.3 gpm to activate its heating elements. It can also put out a maximal flow of 4.8 gpm. This provides continuous hot water for two faucets and a shower. However, just as with other tankless water heater brands, the flow rate depends on temperature difference between the incoming cold water and the hot water coming out of the unit. According to some experts, if you live in a very cold area this unit may not work as well as in warmer climates. This is true of other tankless water heaters as well, not just the Rheem.
The RTEX 13 uses a rugged brass and copper immersion heat exchanger. It is an energy efficient water heater that modulates power consumption while providing a continuous hot water supply. It is a 13-kilowatt heater that requires 240 volts and 54 amps of electricity. However, 54 amps is quite a high energy draw, and just like with most electric tankless water heaters, you need to install a 60-amp breaker box or the RTEX 13 may trip your regular breaker and dimming house lights.
The Rheem RTEX 13 is a space-saving electric tankless water heater to replace bulky, inefficient water heaters. Although it is energy efficient, you have to modify your home electricity to supply 240 volts and 60 amps. Unlike the EcoSmart ECO 27, the RTEX 13 is not optimal for cold climates, but it works great for a garage, office, boat, RV or double-occupant house.