Very Impressed with the professional service. Explained clearly the process and any problems encountered.
Matching Kilowatt Ratings with Your Breaker...
Is your shower not performing as well as it used to—or has it stopped working altogether? If you're thinking of upgrading or replacing it, this guide is here to help. And remember, if you're ever unsure, don’t hesitate to ask for advice before buying a new unit—getting it right the first time is safer and often saves money in the long run.
Why the Right kW Rating Matters
When selecting a new electric shower, one of the most important things to consider is the power output—measured in kilowatts (kW)—and whether your home's electrical system can safely handle it. The higher the kW rating, the more powerful the shower, meaning hotter water and better pressure. But it also means a higher electrical demand, which needs to be matched correctly with the circuit breaker in your consumer unit.
Here’s a rough guide:
- 8.5 kW shower: Needs a 32-amp breaker
- 9.5 kW shower: Needs a 40-amp breaker
- 10.5 kW shower: Needs a 45-amp breaker
- 12.5 kW shower: Needs a 50-amp breaker
⚠️ Just because your old shower was, say, 9.5 kW doesn’t automatically mean you can replace it with the same—or a more powe ful—one. Always double-check first.

Checking Your Existing Setup
Before heading out to buy a new shower, take a moment to check your current setup:
- Find the consumer unit (fuse box), usually located under the stairs, in a utility room, or garage.
- Locate the shower circuit breaker, which should be clearly labelled.
- Check its rating, which will be printed on the breaker itself (e.g. 32A, 40A).
This tells you the maximum kW your new shower can safely be, assuming the cabling is also suitable.
Don’t Forget the Cable Size
The cable powering your shower is just as important as the breaker. Installing a more powerful shower without checking the cable size can be dangerous. Here’s a quick guide:
- 6mm² cable: Generally supports up to 9.5 kW
- 10mm² cable: Suitable for up to 12.5 kW
If you're unsure what size cable is installed, this is definitely something an electrician should check before you upgrade.
Why It’s Best to Call a Professional...
While it’s great to understand the basics, fitting or upgrading an electric shower involves serious electrical work. Our team of qualified electricians can:
- Check your current breaker and cable
- Make safe upgrades if needed
- Ensure everything meets UK electrical safety standards
And it goes without saying—electricity and water do not mix well. Poor connections or incorrect installations can be dangerous. Don’t take any chances.
Final Thoughts
Choosing the right electric shower isn’t just about picking the most powerful one you can find. It’s about making sure your home can handle it safely. By checking the breaker and cable sizes—and getting the help of a professional—you’ll enjoy a reliable and safe shower for years to come.
If you're in Newton Abbot, Torquay, Paignton, Teignmouth, Bovey Tracey, Chudleigh, or anywhere across South Devon, and thinking about upgrading your shower or need advice, we’re here to help.
At A.M Electrics Devon Ltd, we’re proud to offer friendly, professional service—and you’ll always deal directly with us doing the job. No middlemen, no confusion.
Stay safe, stay warm—and enjoy your shower!