When the water in your electric shower starts going hot and cold without warning, it can be pretty uncomfortable, especially if you are half way through washing your hair.
But it could also mean there is something wrong with your shower unit. Sometimes it might be a simple fix or, as a worst-case scenario, it might need replacing.
One money-saving fix is to replace the old showerhead with one of the best shower heads on the market. While this might be a simple task that can be done yourself, it isn't the only reason your shower might have a problem.
Here, we outline common causes of an electric shower not heating up properly to help you identify your issues and how to fix them.
Thomas Heaney is Design and Technical Manager at NOSA with 18 years' experience in the bathroom industry. An expert in product development, market trends, and customer insights.
Jamie is a highly experienced manager with over 24 years of expertise in the Plumbing & Heating sector. He now brings his knowledge to Build & Plumb, an online retailer, supplying top-quality products for DIYers, renovators, and trade professionals alike.
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Reasons why your electric shower is not heating up
Problems with an electric shower can vary from something simple with a quick fix, to the need for a replacement unit. Most common issues can be resolved quickly and easily – and even if you do need to replace your old electric shower, it shouldn’t break the bank.
1. Incorrect power or temperature settings
If your water temperature is fluctuating between hot and cold, it may be as simple as the settings being incorrect. Thomas Heaney, bathroom expert with Nôsa Bathrooms, explains, “Electric showers rely on the correct balance between power and water flow.”
He adds, “Most units have power settings such as low, eco and high, alongside a separate temperature control. If the power setting is too low and the temperature is set too high, the shower may struggle to heat the water quickly enough, resulting in bursts of hot water followed by cold.”
If you are having this problem, Heaney suggests the following: “Adjust the power setting and slightly reduce the temperature. This usually allows the shower to maintain a steady, comfortable temperature.”
Try different combinations to help ensure you’ve covered all bases. If unsuccessful, you’ll need to move on and test the other solutions in this guide.
2. Low water pressure/flow
Electric showers need a consistent flow of cold water to work properly. Heaney says, “If water pressure drops too low, the shower may only produce a trickle or fail to heat properly.” He continues, “During winter, increased household demand or system-related issues can highlight pressure problems or air in the pipework.”
However, there may be a simpler issue, as Jamie Heath, plumbing and bathroom expert from Build & Plumb, explains, “It’s also a good idea to check that the mains stopcock valve isn’t partially closed, to allow for sufficient water flow throughout your home.”
If the stopcock is fully open, no water is being used elsewhere, and the water pressure remains low, Heath says, “It may be time to fully replace your showerhead or consult a professional plumber for help.”
3. Limescale build-up
Water constantly flows through a shower when in use, so limescale can be a common issue, especially in hard-water areas, explains Heaney. “Over time, calcium deposits can build up inside the unit and around the heating element, restricting water flow and reducing heat transfer. This often leads to fluctuating temperatures or water that never quite gets hot enough.”
One option is to clean the shower, Heaney says, “Cleaning the shower head and inlet filter can sometimes improve performance, but internal limescale build-up usually requires professional attention.”
However, start by cleaning the shower head and see how that works. Heath says, “Remove the showerhead and descale it by placing it in a mixture of white vinegar and water, or commercial descaler for a tougher limescale.”
4. Tripped thermal cut-out
For your safety, electric showers have thermal cut-out switches. Heaney explains how they operate, “Electric showers are fitted with a thermal cut-out to prevent overheating. If the shower becomes too hot internally, this safety device shuts off the heating element, leaving the water cold.”
To fix this issue, Heath says, “Start by turning off the power supply to your shower, then locate the switch and press the reset button.” He adds, “If your thermal cut-out switch is still faulty after resetting it, then it’s a good idea to contact a professional."
5. Faulty heating element
A heating element heats the water as it passes through the shower. The more they are used and the older they get, the more likely they are to fail and not heat the water as intended. Heaney says, “A failed heating element cannot be repaired and must be replaced.”
He adds, “This involves working on high-voltage electrical components and should only be carried out by a qualified electrician.”
FAQs
How long should an electric shower last?
The lifespan of an electric shower depends on a few factors, explains Karen Wise, Shower expert at Triton Showers: “Electric showers generally last between eight and ten years, depending on usage, maintenance and water conditions.” Obviously, the less a shower is used in a soft water area, the longer it can last.
Wise points out, “Standard electric models usually come with a two-year guarantee, but regular care can extend their longevity.” She adds, “In hard water areas, limescale build‑up can shorten the lifespan of all shower types, so regular cleaning can help keep it running efficiently for longer.”
Karen Wise has expertise in product design, market trends and consumer insights related to showers. With an understanding of the latest innovations and customer needs, she offers expert advice to help homeowners select suitable shower solutions that combine style, performance and efficiency.
How much does a pro charge to install an electric shower?
“When planning a new ensuite or bathroom renovation, the cost of fitting an electric shower can vary depending on the specific requirements of the project,” shares Wise. “However, when replacing an existing Triton model, installation by a Triton engineer may be available for a fee of £125 on selected models.”
Although it’s generally advisable to hire an engineer familiar with a particular brand, any qualified personnel can tackle the job. Labour costs will be around £150-£200 for a standard installation. Including a shower and additional pipework can easily raise shower installation costs to £400 or more.
If your electric shower is playing up, it might be time to update so check out our shower room ideas. Alternatively, is it time to invest in a wet room or a walk-in shower? And, designers say 'Shower curtains aren’t dead yet’, so now is the time to get one for your shower space.
