Product Review

Rheem rte 13: Hot Water System Reviews

by Matt Moran

When it comes to electric tank-less water heating systems, Rheem is one of the more popular brands and this isn’t by fluke. The Rheem rte 13 review heater by the popular manufacturer paints a perfect picture of what a high-performance, yet compact heater should resemble and function. It is a top seller on Amazon and it’s not that hard to see why.

Designed to deliver hot water on demand, the RTE 13 is a great energy and water saver. It can also be used to supply hot water to the rest of the house if you so wish – as long as you get the water flow adjustments right. In a nutshell, this is one of the best electric water heating systems currently and below, we take a look at why this is the case. Enjoy!


Before diving right in, it is worth noting that the RTE 13 is an affordable, electric water heater designed for point-of-use applications at home. This makes it a highly efficient system that can significantly reduce your energy bills, while saving on water to ice the cake. If you are wondering how it manages to achieve all this without compromising on efficiency, here is an in-depth look at the specs.

Flow Rate

The manufacturer is known to adopt the exclusive low-flow activation technology on all its tank-less water heating systems and the RTE 13 is no different. It only requires an adequate minimum flow of 0.4 gallons per minute to activate the heater coils.

Generally speaking, the minimum flow rate is more than enough to keep your pipes from freezing, yet little enough to save water in other Conversely, the RTE 13 delivers a maximum flow rete of a whopping 4 gallons per minute and considering that most shower heads consume an average of 2.5 gallons per minute, you should be just fine regardless of application.

Brass/Copper Heat Exchanger

Performance is one of the RTE 13’s main strengths and this is well enhanced by its rugged brass/copper heat exchanger. Scientifically speaking, copper wields higher thermal conductivity compared to most metals and hence, heats water relatively fast and more importantly in uniform fashion. Moreover, the material is extremely durable meaning you won’t have to worry about corrosion at some point in time – as you would expect with most products in the niche nowadays. It will achieve the desired heating in optimal fashion – its main purpose.

Point-of-Use Mechanism

Traditionally, home owners had to get accustomed to the conventional tank-oriented systems where water is first heated, prior to being stored in a tank. Besides being slow, this system can prove to be quite costly in regards to the energy bills accrued while heating. The Rheem rte 13 review, however, adopts an efficient heating mechanism that doesn’t require any form of water storage whatsoever. Basically, all flowing water is redirected to pass through high-performance heating components for instant hot water. This not only saves a lot of time, but more importantly, energy being that it will automatically stop power consumption once turned off. The tank-less feature of the RTE 13 is certainly one of its core strengths, especially when compared to conventional heating systems.

On-Unit Temperature Control with LED

While adjusting the preferred water-temperature settings can prove to be a headache with most conventional heating systems, the RTE 13 is extremely easy-to-use; the best part about the using the system. The built-in temperature control unit feature allows the user to easily adjust the temperatures without having to pull the unit or hire a technician to help out. Moreover, it packs LED status lights that indicate essential mode settings such as the active element in use and whether or not it’s on standby mode. In a nutshell, this is one of the more user-friendly products in the niche and if you are really looking for a versatile product with customizable features at your disposal, I would recommend the RTE 13 any given day.

Modulating Power

When it comes to power, the RTE 13 is well packed. It boasts 13KW – 240 V; enough to handle up to 4.0 gallons per minute maximum flow rate. As high as this sounds, the unit isn’t an energy guzzler as you would expect. The modulating technology ensures that the system only operates when a faucet is open meaning it consumes just enough energy to heat water running through that specific faucet. In a nutshell, this is the electric water heating system to save you bucks.


  • Easy installation. Use your DIY skills and user’s manual to quickly set-up the unit without removing the cover.
  • Pocket friendly price tag in comparison to other tank-less electrical heating units of its caliber.
  • Small and compact design that can fit in limited spaces.


  • The gallon per minute rate slows down as the temperature escalates.
  • Not ideal for extra-large homes with plenty rooms.

Frequently Asked Questions

Can the Rheem RTE 13 Tankless water heater be installed in a mobile home?

Answer: The electrical service – enough AMPS - you have will determine whether or not this heater will work in your pre-fab home. It basically requires a 60-amp twin pole breaker to operate in optimal fashion.

Are gas heating systems cheaper than electric water heaters?

Answer: This is a controversial debate that has been going on ever since the inception of tank-less water heaters. Initially, tank-oriented heating units were very expensive to operate - in regards to the energy consumption bills. However, the modulating power technology such as that incorporated in the RTE 13, has made it way cheaper and faster to use electric water heaters.

In Conclusion

When it’s all said, this is an electrical tank-less heating unit I would recommend on any given day. It is affordable, efficient and really reliable. In a nutshell, the RTE 13 by Rheem does what it’s supposed to and that is heat water in record breaking speed. Most home owners have found it to be an ideal replacement for their conventional tank heaters and the best part is, you don’t have to break bank at all.

Matt is a freelance writer, English graduate, & keen traveler from the UK. As a specialist plumbing expert, he enjoys writing about everything there has to do with at-home plumbing products & related problems. When he isn’t writing, he’s usually drinking coffee or planning his next adventure. In his spare time, he also runs his own blog all about digital nomad life.