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Water Softeners

TwinTec S5 Water Softener

5th Generation Non-Electric System · Suitable for 1–3 Bathrooms · 10 Year Warranty

Key Features

5th Generation Technology

Latest twin-cylinder design with improved eco-features

Non-Electric

Powered by water pressure alone — zero electricity costs

Eco-Friendly Cabinet

Made from 62% recycled plastic — saving 84 tonnes per year

10 Year Parts Warranty

Tested to over 1 million cycles with 2 years labour warranty

The TwinTec S5 is the next generation non-electric twin-cylinder water softener, designed and hand-built in Woking, Surrey. Featuring an eco-friendly cabinet made from 62% recycled plastic and ultra-fine 350 micron resin beads, the S5 delivers luxuriously softened water 24/7 for homes with up to 3 bathrooms.

Technical Specifications

Dimensions (H x W x D)495 x 206 x 435mm
Salt TypeMini Curve Salt Blocks (4 x 2.15kg blocks)
Suitable For1-4 bathrooms
Daily Capacity3,000 litres
Peak Flow Rate56 litres per minute
Water Pressure Range1-10 bar (PRV recommended above 6 bar)
Regeneration Time11 minutes
Water Per Regeneration17 litres
Salt Per Regeneration300g
Resin TypeUltra-fine 350 micron beads
Power SupplyNon-electric (water pressure powered)
Warranty (Parts / Labour)10 years parts / 2 years labour
CertificationsWRAS Approved, BS14743 Compliant

Product Description

Next Generation Twin-Cylinder Technology

The TwinTec S5 uses the latest 5th generation water softener technology with its improved design, eco-features and robust testing. With its unique twin parallel cylinder design, one cylinder regenerates while the other continues supplying soft water to your home — ensuring an uninterrupted 24/7 supply. The entire process is powered by your incoming water pressure, with no timers, motors or electrical components.

Eco-Friendly by Design

The TwinTec S5 is the UK’s first eco-friendly water softener. Its cabinet is made from 62% recycled plastic sourced from contact lens manufacturing moulds — saving 84 tonnes of plastic waste from landfill each year. Combined with its non-electric operation and demand-based regeneration, the S5 minimises its environmental impact while delivering outstanding performance.

TwinTec S5 Water Softener installed under a kitchen sink

Ultra-Fine Resin Technology

The S5 features ultra-fine 350 micron resin beads — the best in the industry. This advanced resin formula has a higher exchange capacity than standard beads, making the softener more efficient and reducing salt and water usage. The high-grade resin is ideal for both high and low flow rate applications, ensuring consistent performance across all household demands.

Mini Curve Salt Blocks

The S5 uses revolutionary Mini Curve salt blocks that are 47% lighter than traditional blocks, making them easier to carry and handle. The redesigned salt chamber accommodates 4 Mini Curve blocks compared to the previous model’s 2 standard blocks, increasing the salt capacity and reducing the frequency of refills. All salt must be Grade A certified to BS EN 973 standard.

Hand-Built in Britain

The TwinTec S5 has a proud British heritage, designed, hand-built and individually tested in Woking, Surrey by TwinTec’s water softener experts. The factory has been in the same location for over 40 years. The S5 is WRAS approved and conforms to British Standard BS14743. Rigorously tested to over 1 million cycles at the factory, it is backed by a 10-year parts warranty and 2-year labour warranty from the manufacturer.

Will from Southern Softflow

Book A Free Home Survey Today

Our friendly team will visit your home, assess your water needs and provide a no-obligation quote

What To Expect

1

Speak To Us & Survey

Give us a call or complete our simple 60 second form. We will arrange a free home survey at your convenience.

2

Tailored Solution & Quote

We will visit your home, assess your needs and provide a no-obligation quote for the best solution.

3

Installation

Our experienced engineers will install your new water softener or drinking water system at a time that suits you.

4

Ongoing Support & Salt

We offer ongoing support, servicing and salt delivery to keep your system running smoothly.

Ben Southern working at his desk at the Southern Softflow office
Infinity water softener installed under a kitchen sink with filtration system and copper pipework
Infinity water softener and water filter system installed neatly inside a kitchen cupboard
Southern Softflow engineer delivering Harvey block salt to a customer doorstep

Our Services

We offer a full range of services from sales & installation of water softeners to ongoing maintenance and supplies

Water Softeners

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Drinking Water Systems

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Servicing & Repairs

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Salt Collection & Delivery

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What Our Customers Say

“From the first contact through to survey visit and arranging for installation, this family-run company was excellent, with plenty of communication. The water softener had to be installed in a very restricted space with very difficult to access mains water inlet and drain. However the company plumber found a workaround, even preserving some of the middle shelf in the cupboard concerned. The installation was completed in one morning, working was clean, and the finished job is very neat.”

“We recently had Southern Softwater visit our home to walk us through the available options, and the experience from start to finish was excellent.The initial consultation was clear, informative, and pressure-free. They took the time to understand our needs, explained the different systems in a straightforward way, and answered all of our questions patiently. It felt like they genuinely wanted to help us make the right decision rather than just make a sale.The installation process was just as impressive. The installer arrived on time, was extremely professional, and worked efficiently while keeping everything tidy. He explained how the system works, made sure everything was set up perfectly, and left the area clean once the job was complete.Overall, we’re delighted with both the service and the product. It’s rare to find a company that delivers such a smooth and professional experience from consultation through to installation. Highly recommended.”

“Brilliant service. Survey done clear explanation of product from Ben. Fitting done three days later. Very helpful and tidy technician. Added a hard water tap at the last minute no problem. Would highly recommend the service and product. Thanks guys!”

“Fast response to our enquiry, full information provided, work booked for following week. Fitter arrived on time, pleasant, efficient, very tidy and cleaned up when work finished. Very neat pipework, showed us how to isolate soft water if required at any time, and showed us position of new stopcock. Explained how filter system worked, helped us to set up App for notifications when salt low. Stacked spare salt in garage, advised how to apply for more supplies. Presented us with a delightful gift hamper of locally sourced products. Would highly recommend Southern Softflow Ltd.”

“Fantastic service from the Southern Softflow Team! My enquiry was dealt with promptly and expertly. We were first told by the guy from another local company who installed our water softener (before we owned the property) that the softener couldn’t be serviced reliably as it hadn’t been used for a while and was in any case 10 years old so in need of replacing. We were also told it would be unsafe to use and were quoted a heavy price by him to replace it. Keith from Southern Softflow came to have a look, He was knowledgeable, friendly and very understanding. He spent time analysing the water to make sure it was safe to use. He flushed the system through thoroughly and assured us the softener is in good working order so we wouldn’t need to replace it which was a great relief. Several weeks after Keith’s visit we are using our softener with no issues and are very relieved Southern Softflow operate in our area!”

“Moving home to an area with very hard water, I decided it was time to install a water softener. After research, I chose Southern Softflow, who offered exactly the reassurance and expertise I was seeking. Decision to installation took two days. Installation itself took a little over two hours, was carried out neatly, efficiently, and professionally. The new tri-flow drinking tap looks great in the kitchen, and even though I’ve used Brita filters for years, tea already tastes noticeably better after only 12 hours. Many thanks to Ben, Will, and the team, greatly appreciated. A full 10 out of 10.”

Emily, a Southern Softflow customer, sharing her testimonial in her kitchen

Are You Fed Up With The Impacts Of Hard Water?

Emily was looking to protect her new build home in Shaftesbury, Dorset from the impacts of limescale. After living in her new house for two years ago and consequently became frustrated with the impacts of limescale.

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