Many of our electric showers are available in a range of different kilowatt power ratings, ranging from 7.5kW up to 10.5kW - ratings are lower for Instaflow water heating and Instaflow T30i handwash units.
But what does this mean to me?
Basically the higher the kW rating -- the higher the flow of water from your shower head.
For example — a 7.5kW shower giving a 40-degree Celsius shower in winter will deliver a flow rate of around 3 litres per minute. By comparison, a 10.5 kW shower can give 50% more flow from the shower head than a 7.5kW shower. Our short video demonstrates what this difference looks like.
What should I check for before selecting a power rating?
Before selecting your unit's power rating, you will need to check the following;
Water pressure and flow rate
Rating of the miniature circuit breaker or fuse in your consumer unit
Size of electric cable running to your shower.
A higher kilowatt shower will have greater installation requirements than a lower kilowatt shower, therefore, you may need to upgrade your shower's electrical system to support a higher kilowatt shower.
The table below shows an example of the different typical requirements for a 7.5kW and a 10.5kW shower.
7.5kW electric shower
10.5kW electric shower
(bar/litres per minute)
1 bar delivering 8 l/min
1.5 bar delivering 11 l/min
Miniature circuit breaker (MCB) rating (Amps)
Cable size (mm²)
How do I find my existing shower's power rating?
You can find your existing shower's power rating (kW) by checking the rating label on the underside of your electric shower unit (near the shower hose outlet). It should appear similar to the below example.
Need more assistance?
No problem, get in touch with our expert team via phone or email (see contact us), or use our live chat to speak to an advisor and get your queries answered.