---
product_id: 322325986
title: "18kW 240V Tankless Electric Water Heater, Gray"
brand: "rheem"
price: "KSh216700"
currency: KES
in_stock: true
reviews_count: 5
category: "Rheem"
url: https://www.desertcart.co.ke/products/322325986-18kw-240v-tankless-electric-water-heater-gray
store_origin: KE
region: Kenya
---

# 18kW high power output 4.4 GPM flow rate ±1° LED digital thermostat 18kW 240V Tankless Electric Water Heater, Gray

**Brand:** rheem
**Price:** KSh216700
**Availability:** ✅ In Stock

## Summary

> 🔥 Endless hot water, zero wasted energy — upgrade your flow game!

## Quick Answers

- **What is this?** 18kW 240V Tankless Electric Water Heater, Gray by rheem
- **How much does it cost?** KSh216700 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.ke](https://www.desertcart.co.ke/products/322325986-18kw-240v-tankless-electric-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

- • **Space-Saving Minimalism:** Compact design 90% smaller than traditional tanks fits discreetly anywhere, even under sinks.
- • **Energy-Smart Self-Modulation:** Automatically adjusts power to match your hot water demand, cutting energy waste by up to 50%.
- • **Precision Temperature Control:** External digital thermostat with LED display ensures exact hot water temps to the degree.
- • **Durable Copper Heating Elements:** Field-serviceable dual copper immersion elements built for long-lasting, reliable performance.
- • **Effortless Installation & Replacement:** Threaded 3/4 inch NPT water connections simplify setup and future maintenance.

## Overview

The Rheem 18kW 240V Tankless Electric Water Heater delivers continuous hot water on demand with a sleek, compact design that saves space and energy. Featuring precise digital temperature control, advanced self-modulating technology, and durable copper heating elements, it supports up to 4.4 gallons per minute flow rate. Ideal for single shower or mid-range whole-home use, this unit reduces energy consumption by up to 50% compared to traditional tanks, making it a smart, modern upgrade for efficient, reliable hot water.

## Description

This tankless electric water heater is ideal for mid-range whole-home applications. This unit is ideal for single shower applications in the Midwest. The Rheem Performance tankless electric water heaters offer a continuous, endless supply of hot water. A lower kilowatt unit can provide hot water on demand for single or multiple point-of-use applications while a higher kilowatt unit could provide hot water for a whole house depending on the inlet ground water temperature. Tankless electric water heaters save space, save energy, save money, and require no venting. The sleek, compact size, 90 percent smaller than a tank, allows you to save space and place the unit wherever you want, including under a sink. Tankless units only draw energy when hot water is flowing, while traditional tanks are constantly drawing energy to keep the water in the tank at the desired temperature. Rheem's self-modulating technology can save Up to 50 percent on your water heating bill.

Review: Great product, have been using ours for 2 years and it works great.
Review: Bastante cumplidor aun para lo que yo esperaba ya que solo requiero una cantidad relativamente baja de agua caliente y da bastante mas de lo esperado, totalmente recomendable

## Features

- External digital thermostatic control with LED display (+/1 degree accuracy)
- Most advanced self-modulation, adjust power to meet hot water demand
- Durable Copper immersion two heating elements, field Serviceable. Flow Rate- up to 4.4 GPM
- Simple installation – bottom 3/4 inch NPT water connections
- Threaded for easy replacement, simple installation, digital temperature display

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B01MR7Z39V |
| ASIN  | B01MR7Z39V |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #56,282 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #85 in Water Heaters |
| Color | Gray |
| Customer Reviews | 4.2 4.2 out of 5 stars (1,985) |
| Customer reviews | 4.2 4.2 out of 5 stars (1,985) |
| Date First Available | 2 March 2017 |
| Date First Available  | 2 March 2017 |
| Finish | Stainless Steel |
| Flow Rate | 4.4 Gallons Per Minute |
| Included components | Fittings, Aerators |
| Installation Method | Wall Mount |
| Is Discontinued By Manufacturer  | No |
| Item Package Quantity | 1 |
| Item Weight | 6.7 Kilograms |
| Item model number | RTEX-18 |
| Item model number  | RTEX-18 |
| Manufacturer | Rheem |
| Manufacturer  | Rheem |
| Material | Stainless Steel |
| Maximum Pressure | 150 |
| Part number | RTEX-18 |
| Pattern | Minimalist, Modern |
| Plug Profile | Wall |
| Power source type | AC Power |
| Product Dimensions | 46.99 x 36.83 x 8.89 cm; 6.7 kg |
| Product Dimensions  | 46.99 x 36.83 x 8.89 cm; 6.7 kg |
| Shape | Rectangle |
| Size | Small |
| Special Features | LED Display |
| Specific uses | Inside; Professional |
| Style | Heater |
| Voltage | 240 Volts |
| Water Consumption | 7 Gallons |
| Wattage | 18000 watts |

## Product Details

- **Brand:** Rheem
- **Capacity:** 18 Gallons
- **Power source:** AC Power
- **Product dimensions:** 36.8W x 46.4H centimeters
- **Special features:** LED Display

## Images

![18kW 240V Tankless Electric Water Heater, Gray - Image 1](https://m.media-amazon.com/images/I/91J18WlAKqL.jpg)

## Questions & Answers

**Q: will this supply two showers, washer and dishwasher for two people? (1000 sf house)**
A: Hello-

Sizing an electric tankless is very difficult. I always recommend that you call Rheem at 800-432-8373 to get a suggestion. I want to say this will only keep up with ONLY 1 source of hot water at any one given time.

That being said, the RTEX-18 performance ( @240V )-
1.5GPM - 82degree rise
2.0GPM - 62degree rise
2.5GPM - 49degree rise
3.0GPM - 41degree rise

So.... what it can keep up with all depends on:
-the temp of water coming into the house
-the flow rate of each faucet/shower head/washing machine/source of hot water
-outlet temp desired

I hope this helped :)
Ben

**Q: How many amps**
A: Paperwork says it requires four 40 amp breakers or two DP 40 amp breakers. Max draw of 75 amps.

**Q: Rheem rtex-18  be big enough to heat water in my shop to wash my hands and perhaps take a shower in kansas city, mo?**
A: Yes you could even go with the unit rtex-15 one smaller if that's it. Good luck

**Q: how many breakers and what amp.**
A: The RTEX-18 (240 Volt) requires (2) 40 amp breakers and 8 AWG wire.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by B***K on 10 August 2025*

Great product, have been using ours for 2 years and it works great.

### ⭐⭐⭐⭐⭐ Review
*by J***V on 8 December 2023*

Bastante cumplidor aun para lo que yo esperaba ya que solo requiero una cantidad relativamente baja de agua caliente y da bastante mas de lo esperado, totalmente recomendable

### ⭐⭐⭐⭐⭐ Review
*by A***R on 1 April 2022*

The unit was easy to install and I use the existing hot water tank as a preheat tank. We are on a well and the water is very cold coming up out of the ground, so I set the tank at minimum and it heats the well water to roughly ambient temperature. My gas bill has dropped by 70% and my electric bill has only risen about 3%. This is the only way to go!

## Frequently Bought Together

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*Product available on Desertcart Kenya*
*Store origin: KE*
*Last updated: 2026-02-04*