---
product_id: 38503297
title: "Rheem 240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY"
brand: "rheem"
price: "$656.95"
currency: USD
in_stock: true
category: "Rheem"
url: https://www.desertcart.us/products/38503297-rheem-240v-heating-chamber-rtex-13-residential-tankless-water-heater
store_origin: US
region: United States of America
---

# 13kW high power output Up to 4.8 GPM flow rate ±1°F precise digital temp control Rheem 240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY

**Brand:** rheem
**Price:** $656.95
**Availability:** ✅ In Stock

## Summary

> 🔥 Never settle for lukewarm—experience precision heat on demand!

## Quick Answers

- **What is this?** Rheem 240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY by rheem
- **How much does it cost?** $656.95 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/38503297-rheem-240v-heating-chamber-rtex-13-residential-tankless-water-heater)

## Best For

- rheem enthusiasts

## Why This Product

- Trusted rheem brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Compact Powerhouse:** Sleek wall-mounted design fits seamlessly into any space without sacrificing performance.
- • **Energy-Smart Heating:** Boasts an impressive 99.8% energy efficiency, saving you money while reducing your carbon footprint.
- • **Easy DIY Installation:** Includes 1/2 NPT adapters and compression fittings for a hassle-free setup that professionals and savvy homeowners love.
- • **Instant Hot Water, Always:** Tankless technology delivers continuous hot water on demand—no more waiting or running out.
- • **Precision at Your Fingertips:** External LED display with ±1°F accuracy lets you dial in your perfect temperature effortlessly.

## Overview

The Rheem RTEX-13 is a 240V electric tankless water heater featuring dual copper immersion elements and a digital thermostatic control with ±1°F accuracy. Delivering up to 4.8 gallons per minute at 13kW power, it offers 99.8% energy efficiency and a compact wall-mount design, perfect for modern homes seeking instant, reliable hot water with easy installation.

## Description

Professional classic® tankless electric water heaters offer continuous hot water quick and on demand for single point-of-use or multiple applications

## Features

- External adjustable digital thermostatic control with LED display (+/1 degree accuracy
- Durable Copper immersion two heating elements, field Serviceable.Self-modulating power control
- Simple installation – 1/2 NPT adapters included; side 1/2 inch Compression water connections
- 99.8% energy efficient. External controls to adjust temperature in increments of 1°f. Water-Saver Shower Head – 1.5 GPM
- Threaded for easy replacement, simple installation, digital temperature display 54 A. 13kW Model Flow Rate: up to 3.17 GPM
- 54 A

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B01NAUZJPE |
| Best Sellers Rank | #51,940 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #45 in Water Heaters |
| Brand Name | Rheem |
| Capacity | 1.5 Gallons |
| Color | Gray |
| Customer Reviews | 4.4 4.4 out of 5 stars (1,397) |
| Efficiency | at least 99.8% energy efficient |
| Flow Rate | 4.8 Gallons Per Minute |
| Global Trade Identification Number | 00020352685328 |
| Heat Output | 13 Kilowatts |
| Included Components | Rheem RTEX-13 Residential Tankless Water Heater |
| Is Electric | Yes |
| Item Depth | 0.5 inches |
| Item Dimensions W x H | 8.25"W x 12.62"H |
| Item Type Name | Rheem RTEX-13 Residential Tankless Water Heater |
| Item Weight | 1.8 Kilograms |
| Manufacturer | Rheem |
| Manufacturer Part Number | RTEX-13 |
| Material Type | Copper |
| Maximum Temperature | 140 Degrees Fahrenheit |
| Model Number | RTEX-13 |
| Mount Type | Wall |
| Power Source | Electric |
| Special Features | LED Display |
| Style Name | Heater |
| UPC | 020352685328 |
| Unit Count | 1.0 Count |
| Voltage | 240 Volts |
| Wattage | 13 KW |

## Product Details

- **Brand:** Rheem
- **Capacity:** 1.5 Gallons
- **Power Source:** Electric
- **Product Dimensions:** 8.25"W x 12.62"H
- **Special Feature:** LED Display

## Images

![Rheem 240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY - Image 1](https://m.media-amazon.com/images/I/31ivMdN84FL.jpg)

## Questions & Answers

**Q: How many amps are needed for rheem rtex - 13 240v heating tankless electric water heater**
A: Hello-The RTEX-13 requires 1x 60A@240V breaker / 6 AWG recommended wire size.Specs - http://cdn.globalimageserver.com/fetchdocument-rh.aspx?name=Specification-Sheet&id=fc3235b7-7cd0-42cd-93bc-7169ea92be31 Rheem 800-432-8373I hope this helped :)Ben

**Q: Do these tankless water heaters require an overflow line to the outside of the home or a pan like is required on normal water heaters ?**
A: No tank, so, no overflow line required. It mounts on the wall. A pan is needed if required by building code in your city.

**Q: We have a 500sq' apt. 1 kitchen sink, 1 lav sink and tub/shower. This tankless heats water to both sinks but nothing to the tub/sh. Help**
A: Sinks have aerators to slow down the water where a tub doesn't. It sounds like one possibility is that your exceeding the GPM for this heater. Next possibility, double check an measure your actually getting at least 240v at the heater, I had an issue where my unit was only getting 235v an it was causing a similar issue where only one of the two heating elements was activating. I had it set to 125F but it was coming out 100F. It was warm and without a meter I would of thought it was working correctly until I tried filling a tub. It couldn't even get the water warm. 
I pulled my wires out an restripped an cut an screwed them in an it fixed my problem, now its measuring around 245v. Make sure there is no copper showing after screwing down your input wires.

Now filling the tub I noticed after about 10-15 seconds the water gets too hot to touch. I set it to 135F.

**Q: El titan n270 me puede alimentar 3 baños y agua caliente en toda la casa.**
A: Solo tengo un baño y me sirve muy bien el calentador. Mi casa es pequeña. I'm sorry.

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-07-13*