What is a SESI?

Though other devices have similar compression fittings to SESI, this electolytic scale inhibiting device is carefully designed with a double hex at each end, improving grip for installers. This allows for faster installation and minimises the risk of damaging the product during installation.

SESI electrolytic scale inhibitor has a zinc anode, offering whole property protection. Once the limescale crystals have had their structure altered through the electrolytic process, they remain unable to stick to one another or to surfaces throughout the entire system.

Is SESI Reliable?

Electrolytic devices are identified in the Building Regulations Compliance Guide for Part L as an approved method for preventing the build up of limescale. The performance of SESI has been verified by independent studies and the device outperformed two major competitors in comparative tests.

SESI is manufactured in theUKto TUV accredited standards and is designed to last for 10 years. It comes with a 5 year guarantee and is approved by the Water Regulations Advisory Scheme (WRAS).

It is a high-quality, long-lasting solution to the problem of limescale build up.

Part L

The UK Building Regulations Part L covers the conservation of fuel and power and has been recently updated to place a greater emphasis on improving the energy efficiency of homes.

This is as a result of upcoming carbon emissions targets set by the Government, and hard water areas have been identified as an area in particular where efficiency levels could be improved.

The Building Regulations Compliance Guide

Written to assist installers, the UK Building Regulations Compliance Guide suggests how best installers of heating and hot water systems might comply with the Regulations with regards to hard water. It recommends that:

'Where the mains water hardness exceeds 200 parts per million, and if required by the manufacturer, provision should be made to treat the feed water to water heaters and the hot water circuit of combination boilers to reduce the rate of accumulation of limescale.'

SESI and Part L

The Guide suggests several ways of achieving compliance with Part L, stating that limescale

'can be controlled by the use of chemical limescale inhibitors, combined corrosion and limescale inhibitors, polyphosphate dosing, electrolytic scale reducers or water softeners.'

There are notable drawbacks to some of these methods. Water softeners, for instance,require regular regeneration and periodic maintenance. They can be expensive; unappealing for customers. Polyphosphate devicesare suitable for protecting an entire property, but they too are expensive and involve chemical dosing.

Electrolytic Scale Inhibitor Devices

Unlike other methods of regulating scale build up, electrolytic scale inhibitors offer all of the following benefits: 

• level of protection - can be installed to protect an entire property or a single appliance, as required.
• life of the device - approximately 10 years.
• no maintenance required after installation.
• no pollutants released into the system.
• low initial and ongoing costs.
• easy installation.

Electrolytic scale inhibiting devices such as SESI offer a hassle-free solution for both installer and homeowner to improve compliance with Part L and save money by reducing limescale build up.

Saving Money with SESI

It's not only inconvenient to live with hard water problems, it's also more expensive. British Water claim that '1.6mm of scale in heating systems causes a 12% loss in heat transfer from the energy source (gas, electricity) to water, ie in heating efficiency.'

Imagine the impact of this on your energy bills.

This is a hidden cost which many homeowners don't realise they are paying. By restoring the effectiveness of your system with SESI, you could save up to £100 a year off your energy bills.

The Benefits

The average life of a boiler heat exchanger is 10-15 years. In hard water areas, this can be cut by nearly 80%, reducing the life expectancy to just 2-3 years.

By installing a SESI, you can restore system efficiency and minimise the damaging effect that scale has upon appliances and system components.

• Reduced fuel bills.
• Reduced emissions.
• Prolonged life of heating system and appliances.
• Cost-effective.
• Protects an entire property.
• Long-life.
• Environmentally-friendly.
• Requires no power supply or chemical dosing.
• Requires no maintenance after installation.

SESI is Now Available to Buy.

As the unit must be installed by a qualified heating & plumbing engineer, we advise homeowners to contact their local plumber to source a SESI through them.

If you are a qualified plumber, a SESI unit can be purchased from all major merchants and stockists such as Plumb & Parts Centre, Grahams, PTS, Plumb Base and City Plumbing. Or contact your local independent distributor.

To find your nearest stockist simply download the FREE SESI APP which will locate your nearest merchant via your postcode. Available on Google Play and Apple App Store.

Important - WRAS Installation and Requirements and Notes

The SESI unit must be installed in accordance with WRAS installation requirements IRN R120 and IRN R150. Further information is available from the Water Regulations Advisory Scheme.

Step 1

Close the stopcock to the incoming cold water mains supply. Check that the water is turned off by opening the nearest cold water tap.

Step 2

Position the SESI in a straight section of the pipe, after the stopcock and before the system branches. Measure the correct length of the model being fitted and mark the pipe.

Step 3

Remove this section with a hack saw or pipe cutter. Take care that the ends of the pipe are square. A small amount of water may spill from the pipe so have a cloth and bowl close by.

Step 4

Clean up the ends of the pipe with a file and/or wire wool so that they are clean and smooth.

Step 5

Place your SESI into the gap and connect to the pipe ends using the compression fitting provided. Ensure the joints are firm.

Step 6

Open the stopcock and check for any leaks. Your SESI unit is now operational.

Sizes available:

Domestic systems: 15mm, 22mm

Commercial applications: 28mm, 35mm, 42mm, 54mm

All models are complete with robust compression fittings for easy connection. If the pipe in your systems is of a different diameter or non standard material, consult a plumber before attempting to fit.

For the full technical specification document and installation instructions please download them HERE.

Technical specification.

Connection: 15mm* compression / 22mm compression
Design flowL 0-25l/min (1.5m3/hr) / 0-37l/min (2.22m3/hr)
Length: 195mm / 195mm
Weight: 0.53kg / 0.61kg
Test regulations: (UK) WRAS Certification 0107038

*Removal of compression fittings converts unit to ½" BSP

Materials Used

Outer body: copper
Anode material: pure zinc & magnesium

Click Here to download the full technical specification

What is limescale?

The municipal water supplied to approximately 65% of the UK population is hard water, containing natural calcium and magnesium mineral salts. Although these minerals are not harmful when we drink them, they can cause harmful scale and deposits in pipes and appliances. When hard water is heated, these dissolved salts can separate out, clinging to the nearby surfaces and forming a head layer of scale. In pipes, this layer of limescale slows down the flow of water and may eventually block the pipe completely. In boilers, washing machines, kettles and other appliances, it builds up on the heating elements or heat exchangers, reducing efficiency and shortening the useful life of the equipment. Also, limescale settling out from the hard water will often lead to deposits around taps and showers which can be difficult to remove.

Where is hard water in the UK?

How is hard water measured?

Hard water is measured by the amount of calcium and magnesium salts in your water. This is expressed in the UK as parts per million (ppm) as follows:

If total water hardness exceed 200 ppm steps should be taken to treat the feed water to water heaters and the hot water circuit of combi boilers to reduce the rate of accumulation of limescale.

How do I know how hard my water is?

In terms of measurement your water provider will advise how hard your supply is or you could use a simple colour test strip. These are available through plumber's merchants. The most visible sign in your household is usually the kettle where you would see clumps of scale in the water or baked onto the element.

What Does SESI do?

The SESI electrolytic scale inhibitor prevents limescale in water, particularly useful in hard water areas. The SESI can help prolong the life of appliances and prevent pipes from being blocked.

How does SESI work?

SESI works by electrolytic action. This involves the interaction of two metals in the unit, the copper body (cathode) and the zinc (anode). It has the effect of releasing zinc irons into the water which change the structure of the hard salt crystals (calcium) that cause scaling. This causes the crystals to cling to each other rather than appliances or pipes. They are simply flushed through the system or simply wiped away.What is the difference between electrolytic and magnetic devices?

Magnetic devices are claimed to prevent scale on an individual appliance such as a washing machine, dishwasher, coffee machine, vending machine etc. Though they are environmentally friendly, non-polluting and easily connected to the incoming mains water pipe, their effectiveness has not been scientifically proven. The magnetic device cannot be used to treat the whole house, nor for stored water and will not stop scale in static situations such as a boiling kettle.

Where is SESI fitted?

The unit should be installed in the rising main of the municipal water supply, so that the whole property is protected. If the device is fitted to protect only a single appliance, there should be at least three metres of water pipe between the SESI unit and the appliance.

Further Information

For more information on Salamander products please visit www.salamander-engineering.co.uk