---
product_id: 261635010
title: "240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY"
brand: "rheem"
price: "$805.52"
currency: USD
in_stock: true
url: https://www.desertcart.us/products/261635010-240v-heating-chamber-rtex-13-residential-tankless-water-heater-gray
store_origin: US
region: United States of America
---

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

**Brand:** rheem
**Price:** $805.52
**Availability:** ✅ In Stock

## Summary

> 🔥 Instant Hot Water, Zero Wait – Upgrade Your Flow Game!

## Quick Answers

- **What is this?** 240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY by rheem
- **How much does it cost?** $805.52 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/261635010-240v-heating-chamber-rtex-13-residential-tankless-water-heater-gray)

## 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 & Powerful:** Space-saving 1.8 kg unit packs a 13kW punch for rapid heating on demand.
- • **Easy DIY Installation:** Includes 1/2 inch NPT adapters and compression fittings for hassle-free setup.
- • **Durable Copper Elements:** Field-serviceable copper immersion heating elements ensure long-lasting, reliable performance.
- • **Energy-Smart Efficiency:** 99.8% energy efficient design slashes utility bills while delivering endless hot water.
- • **Precision Temperature Control:** Adjust your perfect hot water temp with ±1°F accuracy via sleek LED display.

## Overview

The Rheem RTEX-13 is a compact, 240V tankless electric water heater delivering up to 4.8 gallons per minute of continuous hot water. Featuring a precise external digital thermostat with LED display, durable copper heating elements, and 99.8% energy efficiency, it’s designed for easy installation and reliable, on-demand performance in residential settings.

## Description

240V Heating Chamber RTEX-13 Residential Tankless Water Heater, GRAY

## 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 |
|---------------|-------|
| Manufacturer | Rheem |
| Part number | RTEX-13 |
| Item Weight | 1.8 Kilograms |
| Product Dimensions | 32.08 x 20.96 x 9.22 cm; 1.8 kg |
| Item model number | RTEX-13 |
| Size | Compact |
| Color | Gray |
| Style | Heater |
| Material | Copper |
| Item thickness | 1 Inches |
| Power source type | Electric |
| Voltage | 240 Volts |
| Wattage | 13 KW |
| Item Package Quantity | 1 |
| Flow Rate | 4.8 Gallons Per Minute |
| Maximum Pressure | 8 Bars |
| Plug Profile | Wall |
| Special Features | LED Display |
| Included components | Rheem RTEX-13 Residential Tankless Water Heater |
| Batteries Included? | No |
| Batteries Required? | No |

## Product Details

- **Brand:** Rheem
- **Capacity:** 1.5 Gallons
- **Power source:** Electric
- **Product dimensions:** 25W x 25H millimeters
- **Special features:** LED Display

## Images

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

## Available Options

This product comes in different **Style** options.

## 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: 2026-02-14*