What Is an Electric Shower and How Do They Work?

A good shower is more than just a daily routine—it’s an essential part of our well-being. Whether it’s to invigorate us in the morning or help us unwind after a long day, the right shower can refresh both body and mind. But have you ever wondered what makes your shower tick, especially if it’s an electric shower?

Electric showers are a modern marvel that ensures hot water on demand, even if your home’s hot water system is out of commission. Understanding how it works will help you understand if it will be a good fit for your needs. In this blog, we define what an electric is and then we’ll look at how they work, followed by answering some frequently asked questions that our professional plumbers are often asked about these specific types of showers.

What Is An Electric Shower?

An electric shower is a type of shower that heats water on demand using electricity rather than relying on your home’s central heating system or hot water tank. It works by drawing cold water directly from your mains supply and heating it as it flows through an internal heating element within the shower unit.

From the outside, an electric shower looks similar to a standard shower but features a compact box mounted on the wall near the showerhead. This box houses the heating element and controls, making it an all-in-one unit. Its unique design allows it to be installed in almost any bathroom with access to a mains cold water supply and an electrical connection, making it a versatile option for homes with diverse plumbing systems.

One of the main benefits of an electric shower is its independence from your home’s boiler or hot water supply. This means you’ll never face the dreaded cold shower because someone used up all the hot water or turned on a tap elsewhere in the house. Additionally, electric showers maintain consistent water temperature and pressure, even in homes with low water pressure, although they don’t deliver the same powerful flow as some high-end power showers.

While older models of electric showers were often criticised for their weak performance, modern electric showers tend to be more efficient and capable of delivering a satisfying shower experience. Their adaptability and convenience make them a popular choice, especially in properties with limited access to hot water or older plumbing systems.

For more information about the benefits of electric showers, check out our blog entitled Power Shower vs Electric Shower.

How Do Electric Showers Work?

Electric showers connect to your cold-water supply and work by heating this cold water on demand as it passes through the shower unit, much like how a kettle heats water. Each electric shower contains its own heating element in its own tank. The process is straightforward and highly efficient, ensuring you get hot water whenever you need it, without relying on your home’s boiler or hot water tank.

When you turn on the electric shower, cold water from your mains supply enters the unit. Inside, it flows through a heating element, similar to the element in a kettle. As the water makes contact with the heated element, it warms up almost instantly before being delivered through the showerhead.

To control the water temperature, electric showers typically have built-in thermostats and settings that adjust the amount of water flowing over the heating element. For instance:

Higher Flow Rate:

More water passes over the element, leading to cooler water because it has less time to heat.

Lower Flow Rate:

Less water flows over the element, allowing it to heat more effectively, resulting in hotter water.

Modern electric showers tend to have a number of power settings in addition to temperature setting. Some advanced models even feature thermostatic controls that maintain a steady temperature, even if water pressure fluctuates, such as when another tap is turned on.

The principle is simple but effective, and just like a kettle heats water quickly (in fact, it is almost instantaneous) and efficiently, an electric shower offers hot water on demand, making it a reliable option for homes without a consistent hot water supply. For safety reasons, they have a number of components installed to prevent them from overheating the water and causing injury so, once you’ve set your desired temperature, you can rest assured that it will not fluctuate.

Need more help with electric showers? Our professional team of plumbers can handle all kinds of shower repairs and installations, so if you are based in our service area and need a fully qualified plumber or heating engineer, contact us today.

Oliver Osmore has been at the helm of Happy Dog Plumbing since it became part of the Maintracts Services family, bringing with him decades of experience in plumbing, heating, and electrical services. As Managing Director of both companies, Oliver is dedicated to ensuring Happy Dog Plumbing continues its proud tradition of delivering exceptional service and innovative solutions to customers.

Oliver’s approachable nature and problem-solving expertise allow him to work closely with customers, offering tailored solutions to even the most complex challenges. He is passionate about upholding the high standards that Happy Dog Plumbing has become known for, ensuring every job is handled with professionalism and care.

Since its founding, Happy Dog Plumbing has been a trusted name in installation, maintenance, and repair services. Under Oliver’s leadership, the company thrives as part of a larger, customer-focused team, staying true to its roots while benefiting from the expanded resources of Maintracts Services.

FAQs

Installing an electric shower is a job best left to a professional, as it involves both plumbing and electrical work to ensure it’s done safely and complies with building regulations. Here’s an overview of the process:

The shower unit is mounted on the bathroom wall, usually near the cold-water mains supply. It’s crucial to place it within easy reach but far enough from direct water exposure to prevent electrical hazards.
The unit is connected to the mains cold water supply, which ensures consistent water pressure. A professional plumber will check for proper water flow rates and ensure the supply is securely connected.
A qualified electrician connects the shower to the electrical supply using a dedicated circuit. The circuit must match the power rating of the shower and include an RCD (Residual Current Device) for added safety.
Once installed, the plumber tests the unit for leaks, ensures correct water flow and temperature, and seals the edges to prevent water ingress.

Electric showers come in a range of power ratings, typically from 7.5 kW to 10.5 kW, and the right one for you depends on your preferences and home setup:

Lower power (7.5–8.5 kW): These showers use less electricity and are often more budget-friendly, but they may not provide as much water flow or heat, especially in colder months when the mains water temperature drops.

Higher power (9.0–10.5 kW): These showers offer better water flow and hotter temperatures, even in winter, but require a stronger electrical supply. They may need upgrades to your wiring or fuse box during installation.

A 9.5–10.5 kW shower is ideal if you want a powerful and reliable performance, while an 8.5 kW unit may suit those looking for energy efficiency or operating in a smaller household. Your electrician/plumber will assess your home’s electrical capacity to determine the highest power rating your system can support.

You need to consider:

Electrical capacity: Your home’s wiring and consumer unit must be able to handle the power demands of the shower. A qualified electrician/plumber can assess whether upgrades are needed.
Household needs: If you live in a busy household where multiple taps are often in use, a higher-power shower ensures consistent performance.
Budget: Higher-power showers may have higher upfront installation costs but offer better heating and flow, which can be worth the investment.

The energy consumption of an electric shower depends on its power rating and how long it’s used. To calculate:

Energy Used (kWh) = Power Rating (kW) × Time (hours)

For example, a 9.5 kW shower used for 10 minutes (0.167 hours) consumes approximately 1.59 kWh. At an electricity rate of 30p per kWh, this would cost around 48p per use.

Electric showers are energy-efficient since they only heat water as needed, but reducing shower time can further lower energy costs.

The main difference is that an electric shower takes its water from the cold-water supply and heats it up itself using its own internal heating element. Whereas a power shower takes both hot and cold water from your water and then adds a pump to increase the flow of water. Find out the details in our Power Shower vs Electric Shower blog.

Their average lifespan tends to be between 8–10 years, but regular maintenance can extend the life of the unit.

Yes, they have built in safety features such as thermal cut-outs, built-in RCDs. Plus, professional installation and maintenance will ensure safe operation.