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ShowerPowerBoosters do not work like a traditional pump and because of this they are perfect for boosting hot and/or cold water from a Fortic or other close coupled tank.
It was proven by the University of East Anglia in 2025 that the flow rates induced by Shower Power Boosters will preserve the stratification within the hot water cylinder. This means that hot water at 60 degrees centigrade at the top of the cylinder does not mix with cold water at 20 degrees centigrade at the bottom of the cylinder – the mixing of hot and cold water in the tank which occurs with traditional pumps is avoided. The forced mixing of hot and cold within the hot water cylinder means that traditional pumps and cheap Chinese pumps can never work with a Fortic Tank.
We knew Shower Power Boosters do a brilliant job when fitted to Fortic Tanks because of the 5 star reviews we get when customers fitted Shower Power Boosters to boost Fortic Tanks. The effect has now been explained using advance hydraulic modelling also.
Fortic or other close coupled tanks are very common in flats and other homes which do not have access to a loft. Many plumbers will advise you cannot boost the hot water from a Fortic Tank and with a traditional shower pump that is true. As well as mixing hot and cold water inside the hot water cylinder, traditional pumps will also drag in air, and cause cavitation. Shower Power Boosters cannot drag in air or cavitate or overheat.
Most of our customers fit just a single SP2B to boost the hot only and they are perfectly happy with just one pump. Because both hot and cold pressures are likely to be low low pressure, we recommend that you boost both the hot and the cold. We recommend you either buy a SP22S to boost the hot and the cold or switch the cold to mains supply and double boost the hot with a SP21S.
When you receive your pump you will receive a fitting guide telling you exactly how to fit the pumps, fitting is something any plumber or competent DIY person can do in minutes. Cut out 110mm of 22mm pipe, slip in a Shower Power Booster, tighten the two compression joints, plug in the transformer, and a problem that you may have suffered with in years disappears in minutes with this plug and play solution.
You might want to try a local plumber on our list if there is one near you:-
Explaining The Options in More Detail
The Shower Power Booster is designed not to overheat, or cavitate, and it will not pull out water at a rate which exceeds the water required for a shower. It will significantly improve the flow to a bath.
You only need 5 to 6 litres of hot water for a good shower and 3 metres head which is achieved by mixing 2/3rds hot with 1/3rd cold. Changing your cold to the shower to mains pressure and just taking hot from the tank with your tank refilling at 4 litres a minute means the cold tank stays full. With boosted gravity hot and cold the tank will drain a little bit quicker but it is often ok.
It’s an easy DIY job, you can fit the pump inline using your existing pipework, and it’s a 10-minute job for most.
OTHER OPTIONS TO DOUBLE BOOSTING THE HOT
If you want to avoid changing the cold to mains pressure and double boosting the hot then fitting a SP22S to single boost hot and cold is an option. Just boosting the hot with a single boost SP2B may need a second pump added later but for some homes that is all you need.
ShowerPower Boosters can be close to your hot water cylinder or close to the shower or tap you want to boost.
Detailed drawings and instructions are in the booklet sent with the pumps but you can download the online version of this guide
Here are links to the pumps you need.
SP21S Double Boost Hot
SP22S Single Boost Hot & Cold
SP2B Single Boost Hot
