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Whole of House Water Filter with Scale Reduction - WH16COMB / WH32COMB

Installing Your Whole House Scale Reduction System

Your new Scale Centurion™ system provides protection from scale formation throughout your home. It can be installed at the point of entry to treat your entire home, both hot and cold water, or can be located directly before a water heater or other device (e.g. sauna, etc) that requires protection from hard water.

Scale Centurion™ reduces or eliminates scale formation on internal and external plumbing surfaces as well as reducing spotting and streaking normally associated with hard water.

The system is complete, self-contained, loaded with media and ready to use. A straightforward inlet and outlet connection is all that is required for installation. We recommend using a professional plumber to install the system. It should take them between one and two hours depending on how much pipe work needs to be altered.

Please Note

1) This unit is designed to work with a maximum / peak flow rate of 16 Litres per minute. If you exceed this rate, while it won’t break the filter, it will simply not work properly. So if you haven’t done so already please do a flow rate check in your property before going to the expense of hiring a plumber. You can see a guide to finding your flow rate on our website (See Help / Guides).

2) Fitting a system by-pass valve is highly recommended so that the unit can be isolated later for cartridge changing or to prolong the life of the filter when not required eg if watering the garden.

3) If you don’t already have one, insist that your plumber fits a Pressure Reducing Valve (PRV) to protect the unit from unexpected water pressure increase. This is very rare but does happen - owing to overnight water utility works etc - and can result in failure / possible flooding. For example the Watts 2282500 costs about £15.

4) If fitting outside the property insulate the system to avoid frost damage. (The unit should not freeze).

5) We make it clear to your plumber in the instructions below that they should USE PLASTIC PIPE and not feed the system from new or cheap COPPER PIPES because the latter will leach copper which risks destroying the Scale Centurion™ anti scale media (turning it bluey / green). If this happens, you would have to buy fresh media. (We tell the plumber, below, that given our clear warnings about this, that they would be liable- but don’t worry, if it comes to it, we will give you a good discount).

This applies to ANY length of new copper - even a few inches of new copper piping for the fitting. If your plumber ignores our instructions then you can simply leave the Scale Centurion™ housing empty for 6 weeks and run water through it until all the copper is oxidised. Then insert the Scale Centurion™ cartridge. (This is a simple DIY job. You shouldn’t have to call the plumber back - but note below re closing the housing unit back up correctly).

6) If you are fitting a double or treble unit etc you must fit them IN PARALLEL (not in series).

7) As per above (1) this unit is designed to work with a maximum / peak flow rate of 16/L per minute. If you exceed this, while it won’t destroy the filter, it simply won’t work. Underestimating the flow rate is the main - indeed the only - cause of any customer complaints about the technology. If you are not sure of your peak flow rate your plumber should be able to help. What you can do is fit these 10 inch housings but get your plumber to leave enough clearance to retrofit 20 inch units should that prove necessary. Rest assured that if the flow rate is below 20L/minute this unit will work fine.

How It Works

Scale Centurion™ prevents scale by transforming the normal dissolved hardness minerals into undissolved crystal micro-particles. These crystals stay suspended in the water and have a greatly reduced ability to react and attach to surfaces like dissolved hardness does. Therefore the problem of internal build- up of scale in pipes, water heaters and on fixtures and glass is greatly reduced.

Please note that Scale Centurion™ is not technically a water softener. Unlike salt softened water, Scale Centurion™ treated water maintains the beneficial essential mineral content of your water and is safe to drink.

Low or phosphate-free cleaning products are recommended to achieve optimum results. Modern surfactant or detergent based, liquid soaps are preferred over old - fashioned caustic solid soaps.

Scale Centurion™ Benefits

• Chemical Free Scale Prevention. Cost savings and environmental benefits.

• Virtually Maintenance Free. No salt bags or other chemicals to buy, transport and store.

• No electricity, no wastewater, completely self-contained.

• Beneficial minerals retained for more healthful drinking water.

• Improves the efficiency of water-using appliances.

• Simple installation – no electrical and drain hookup.

• Safe for landscaping and lawn watering. No need to costly bypass plumbing.

• Compatible with all on-site and community wastewater treatment systems.

• Not subject to water softener restrictions and “bans”

Your Scale Centurion™ system will improve the properties of water throughout your home. Here are some things to expect and some recommendations for maximizing the benefits of Scale Centurion.

Sinks and fixtures - reduced spotting. If water is allowed to evaporate off a surface, small spots may be left behind. If wiped off frequently, the spotting should not require any more than a wet cloth or sponge to remove.No harsh chemical should be required as with typical hard water spotting.

Dishwasher-Spotting on dishes and on the surface of the dishwasher should be greatly reduced. We recommend that you immediately reduce the amount of dishwashing detergent by approximately 50% as compared to hard water use. Dishwashing detergents low in phosphates are highly recommended as they are better for the environment and phosphates can cause spotting. The use of a rinse aid may be advised.

Shower doors and tiles- should have reduced spotting. When water evaporates off a surface, small spots may be left behind. These spots should be easy to remove with a damp cloth or sponge. In very hard water areas treating the shower glass with Rain-X 2 in 1 glass cleaner, or equivalent, will further reduce cleaning requirements.

In the bath you should notice that soaps and shampoos lather more than with un-treated water. Soaps and shampoos will also rinse off much easier and faster than they would with traditional soft water. We recommend the use of modern soaps for the best results.

Things to watch for: During the first 30-90 days:

• Faucet / Tap aerators and drains may plug occasionally as old scale is removed from your plumbing system and water heater.

• You may also see milky water while the descaling is taking place. This is simply an increase in the calcium in the water because Scale Centurion™ is removing old scale deposits from your pipes. It is perfectly safe.

Good practices:

If your dishwasher is severely coated with scale at the time of installation, we recommend that you purchase a good dishwasher cleaner to accelerate the cleaning. After this initial cleaning Scale Centurion™ should keep it clean.

We also recommend that you drain your water heater tank 30 to 60 days after Scale Centurion™ is installed, and again in one year. This is a good practice that can dramatically increase the life of your water heating appliance. If you have an electric “tank type” water heater, for optimum results and higher efficiency, we recommend you change the heating elements to a “low watt density” model.

Please ensure that the watt density is specified at less than 70 watts per square inch, and is compatible with the brand you own. If you can only change one heating element, change the lower unit which operates most of the time.

Scale Centurion™ will help keep the tank and heating elements free of scale and operating at peak efficiency. Please follow the manufacturer’s instructions when draining or servicing the tank!

Cartridge Changes:

Water Filter Cartridge Life: Change every 1 Year Re-order code FIL16

Scale Centurion™ Cartridge Life: Change every 2 Years Re-order code SC16

**Notes for the Plumber**

Please read the customer information above.

What you need: A Bypass, a PRV and connections to the 1 inch BSP ports.

When attaching the pipe connectors we strongly recommend using liquid sealant such as Loctite 577.

If you must use PTFE tape do not overdo it. Use no more than 10 complete wraps of PTFE tape. (While the brass screw thread is robust, if it's over-forced it might crack).

The water enters the filter on the left hand side.

The filter ports are One inch BSP. Do not use tapered males.

The Scale Centurion™ system differs from a conventional softener or media filter in a number of key respects.

The system is light and only partially filled with media. This is normal. The UP-flow operation of the system requires a lot of freeboard to allow the bed to fully fluidize.

  1. A system bypass valve should be installed on every system to facilitate installation and service.

  2. Understand the “important note about iron, manganese and copper” below - especially that leaching copper pipes will damage the anti-scale media.

  3. You must ensure a Pressure Reducing Valve (PRV) is fitted to protect the unit from unexpected water pressure increase.


Make sure the system is level. Because the system operates in an UP-Flow, fluidized bed mode, having a level surface is more important than with a softener or media filter.

When positioning the unit allow enough space underneath for cartridge changes

Where possible leave enough space to retro-fit a “20 inch unit” in case the customer wants to upgrade later. (Total size of a 20 inch unit - incl the same head and bracket as you have now - is 27.5 inches / 70cm. Compared to your current unit ie 17 inches / 43cm). The customer would simply need to screw the 20 inch bottom bowl into the existing head that you’ve fitted.

Do not let the system freeze.


The unit must be closed fully or it might leak - sooner or later. A fully closed housing has a gap of 2mm to 3mm max between the lower blue nut and the blue top. Anything wider than 3mm is definitely wrong.

You can get fairly close to this gap screwing it by hand. Then use the wrench to give it a final tightening. BUT if you need to use a lot of force with the wrench to achieve that 2mm / 3mm then there is a problem. Check the following:

a) The cartridge (that sits inside the housing) must be closed properly eg in cartridges where a slot joins the lid to the lower housing, these must be slotted correctly. (This is very simple to do).

b) For cartridges which screw-tighten these must be fully screwed up

c) The small rubber ring / gasket that sits on top of the cartridge must be seated correctly in its recess / ring.
d) You can test by simulating the assembly of the white sump to the head. (i) remove oring (ii) insert cartridge in the white sump and without using the ring nut (iii) simulate the final tightening position. The system must be able to close without problems.

e) The large thin o-ring must be positioned as sent ie on the higher ridge. Do not put them on the lower ridge ie where you need to stretch them to fit and they are visible when the blue lid is placed onto the white base.



You must NOT immediately feed the SC cartridge 2 from new or cheap COPPER PIPES. These will leach copper and destroy the SC anti scale media. This damage is easily identifiable (media turns to a bluey/green) and your client will require expensive new SC media which they would be within their rights to look to you to replace.

Only put water into the SC cartridge after any copper pipes and flux are at least 6 weeks old and have been oxidised.

This applies to ANY length of new copper - even a few inches of new copper piping for the fitting.

Do not Bypass… RUN IT IN: If you must use copper pipe and flux you must leave the SC housing empty. Simply keep the Scale Centurion™ cartridge CODE SC16C outside the housing and run water through the empty housing for at least 6 weeks to allow any new copper and flux to oxidise.

So “run the system in” by leaving the second chamber empty for 6 weeks

Later, when all the copper and flux is oxidised, you can insert the Scale Centurion™ cartridge. (This is a simple job which your client could do themselves).

During this time the client can still enjoy the benefits of the other filter cartridge which purifies all the water throughout their property.

Using Scale Centurion™ with other water treatment equipment.

Scale Centurion™ must be the last stage in the treatment chain. Do not install any filters after Scale Centurion™ or before any devices for which scale prevention is required. Point of Use filters,e.g. carbon or Reverse Osmosis filters are exempt from this requirement.


Please ensure the housing unit(s) remain in a vertical position while screwing on the top. Otherwise the loose cartridge inside might mis-align and be damaged. This damage will void warranty for the filter cartridge(s).

Do not apply phosphate or any other antiscalant either before or after Scale Centurion™.

Iron and Manganese: Just as with conventional water softening media, Scale Centurion™ needs to be

protected from excess levels of certain metals that can easily coat the active surface, reducing

its effectiveness over time. Public water supplies rarely, if ever, present a problem, but if the water

supply is from a private well confirm that the levels of iron (Fe) and manganese (Mn) are less than 0.3 mg/L and 0.05 mg/L respectively. Copper should be less than 1.3 mg/L.

Copper: Copper usually originates from new copper plumbing upstream of the Scale Centurion™ system. If this condition exists, we recommend waiting 6 weeks before placing the system in operation. This will allow the copper surfaces to be fully flushed and develop a natural protective surface.

If you choose to ignore our message above about not using copper and flux and risk damaging the SC media then to further minimise any problem with excess copper you should avoid applying excess flux on the inner surfaces of the pipe and to use a low-corrosivity water soluble flux listed under the ASTM B813 standard. Once the plumbing connections are complete, remove the Scale Centurion™ cartridge CODE SC16C prior to following the startup procedure and flush the plumbing for at least 10 minutes.

Commissioning the Unit

Once the unit is ready - ie the pipework is completed and flexible hoses attached etc you need to flush the system without the anti-scale cartridge. (This is in the second, right-side housing / last on the line). Simply remove the anti-scale cartridge and carefully let the water enter the filters; Once the water is running clear, install the anti-scale cartridge and flush again for 2 minutes. Some noise will be heard during the flushings.

Check for any leaks. Run the cold water tap nearest to the filter for 5 minutes to release any trapped air. Repeat this process with all other cold water taps in the property and flush any toilets once.


Inlet/Outlet Connection:... 1 inch BSP straight

Temperature:................... 40° - 110°F

pH:.................................. 6.5 to 8.5

Ferrous Iron Max*:.......... 0.3 mg/L

Manganese, Max*:.......... 0.05 mg/L

Copper, Max*: ………….. 1.3 mg/L

Water Pressure: 15 min., 100 max (PSI)

Helpline 020 8761 6611

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