Combimate

The Combimate is due for its annual re-fill but there is still plenty of Siliphos in it, do I still need to change the Siliphos?

Yes. To maintain the treatment effectively both the quantity and quality of the crystals needs to be kept at an appropriate level. Siliphos reduces in volume in proportion to the amount of water passing through the Combimate which will vary according to individual domestic circumstances. Siliphos eventually degrades with water contact and if no water is used at all the crystals would still eventually break up. The Siliphos in the spheres is also absorbed from the inside first which is why the spheres may still appear to be complete when in fact they have been mostly discharged and could be almost hollow. Our recommendation to replace the Siliphos annually provides a simple routine suitable for a range of typical domestic applications; however not every situation will be the same and this will be reflected in the condition of the Siliphos, which is why we recommend the annual change.

Do I need to fit a separate (non-treated) drinking supply?

Combimate is not a water softener. Water softeners generally use salts so softened water requires a separate supply because of the increased salt content. Siliphos is classed as a ‘food grade’ additive which conforms to EN1208 and WHO standards as a safe additive for drinking water. You can therefore install a Combimate directly on the rising cold water main and safely bathe in or drink all the water that has passed through it (provided that the water is not rendered unpotable for some other reason). Combimate deposits Siliphos in minute quantities producing a concentration of about 2 ppm in the passing water compared to an average mains supply of 10 ppm.

Is Siliphos safe for water in contact with babies, tropical fish or skin conditions?

Yes. Siliphos is a ‘food grade’ additive, so water treated with it is perfectly safe for human consumption.

I have a Combimate fitted but still have scale in my showerhead / kettle / taps.

Combimate is not a water softener. Siliphos greatly reduces scale deposits and over months and years will slowly reduce scale which has been deposited before the installation of the Combimate. Siliphos reduces the amount of scale deposits by keeping the minerals which cause scale in a dissolved and suspended state at higher temperatures. As a result most scale-causing minerals pass through the system instead of forming scale deposits on heating elements in boilers, kettles and other appliances. Unlike softened water, water which has passed through a Combimate remains unchanged so hard water treated with Siliphos but left in a kettle or at the end of a shower head may still create a build-up of scale when the water evaporates. Users should therefore empty the kettle after use every time it is boiled to prevent scale build-up or wipe the element (when the unit is unplugged) at least once a month after use. Shower heads may also need to be wiped every few months to remove surface scale residue.

I seem to be getting a film of “scum” on my kettle element or shower head?

This is because the Siliphos is working taking most of the scale out with it. When the water settles, the Siliphos settles with it on the kettle element / showerhead and a thin layer of soft calcium (scale) rests on top of it. This is why we recommend wiping the scale off occasionally (above).

The water seems to be “milky” in appearance

This is nothing to do with the Combimate but because there are some little air bubbles in the water due to the way the hot water system has been set up. You will find that the water will quickly return to its normal state. To confirm that this is the case, fill a glass with water and you will be able to watch the bubbles float to the top and disappear.

My water pressure seems to have dropped since installation of the Combimate

Water pressure can vary for a variety of reasons, including other users elsewhere in the building and also at different times of the day. Installation of a Combimate will reduce water pressure by between 1 and 1.5% which is not normally noticeable to users.

What is the maximum pressure I can install a Combimate on?

100 psi. Every product in the factory is pressure tested to 10bar for additional confidence

My pipe work is 22mm diameter can I still use the Combimate?

Yes. The majority of domestic pipe work is 15mm diameter, hence the use of 15mm fittings. Larger pipe work is generally used to maintain flow rates at lower pressures. Combimates full of Siliphos do not reduce flow to any significant degree and are commonly fitted on 22mm pipe using conventional, pipe-reducing fittings available from any plumber’s merchants.

Can I install Combimate directly on the pipes?

We recommend fixing Combimate onto a wall for absolute security. Some pipes may be insufficiently strongly clamped to ensure a solid installation

Cistermiser’s instructions advise against installing within 45cm of a source of heat. Why is this?

Heat does not reduce Siliphos’ effectiveness but does increase the frequency with which it needs to be replaced. The reason for this is that the rate at which Siliphos dissolves increases as the water supply becomes warmer, so usage rates rise in warm environments such as enclosed boiler cupboards. If possible Combimate should be installed at room temperature and fitted directly onto a cold water supply. If location options are restricted and a warm environment cannot be avoided then the Siliphos content should be checked more often, as frequently as every 3 months.

Can I install the Combimate in an airing cupboard?

Yes. Combimate will work fine in ambient temperatures up to 30°C. The maximum temperature normally reached in an airing cupboard is 25°C. We recommend installing a Combimate as close to the bottom of the cupboard and the cold water entry point as possible.

Will the Combimate protect my central heating system?

No. The water within the central heating is continually circulating and heated / pumped on demand, the only fresh water that enters the system is via a small header tank or pressure top-up link (“filling loop”) to ‘make-up’ for minimal water loss through evaporation. There are proprietary additives (not suitable for drinking water) which can be added to cleanse and protect the system. Combimate is primarily designed to work with potable water.

Does the Siliphos effect last in stored hot water?

If treated water is stored for any appreciable length of time any Siliphos content will eventually leech out into the water so its effectiveness will diminish more quickly than the annual top-up specifies. Combimate is designed for installation with supplies of fresh, incoming water which draws a small quantity of Siliphos through with it as it passes into the system where it is heated. The Siliphos takes the scale producing elements through and out of the system with it.

Do I still need to use salt in my dishwasher?

Yes. Siliphos does not remove the scale-causing minerals from the water so the ‘hardness’ remains unchanged. Similarly if Calgon or similar is used in the washing machine, the practice should be continued.

How is the Combimate different from other water conditioners?

Polyphosphate (Siliphos) has been used for many years internationally as a means of reducing lime scale deposition, particularly when cold water is heated. Other methods to reduce scale deposits have been tried; however the Combimate system is unique in terms of its simplicity, effectiveness, reliability, cost and maintenance. Combimate works by allowing the water to take minute amounts of Siliphos with it into the system. This flows through the system keeping the particles in suspension and preventing them from sticking to the appliance. As a manufacturer Cistermiser initially adopted Siliphos as a proven material with an established record and then focused on the design and development of a patented dispenser to maximise the benefits.

I want to change the Siliphos but cannot unscrew the aluminium ring

Having removed the cover you should then remove the red filler plug to relieve the internal pressure. The aluminium ring should be not more than hand tight although after 12 months or more it can very occasionally ‘bind’ on the plastic thread, if it will not release using both hands we recommend using a filter band such as is used to remove cylinder-type oil filters. A suitable product is sold as ‘Boa-Constrictor’ through D.I.Y. outlets. When replacing the ring it should only be tightened manually.

How do I change the Siliphos? The hole at the top is very small.

To remove the old Siliphos remove the cover from the Combimate, which automatically isolates the water supply and then open the unit by removing the filler plug, retaining ring and dome. Empty the Siliphos from the dome. Reassemble in the reverse order putting the new Siliphos in through the top prior to securing the plug. Before re-assembly, clean the large ‘O’-ring seat before replacing the ‘O’-ring itself. N.B. It is very important to replace the old ‘O’-ring with the new one, which is supplied only in Combimate top-up jars. If the ‘O’-ring is not replaced there is a risk of leakage. Please also remember to send the guarantee sticker / card back to Cistermiser to maintain the guarantee.

I’ve just changed the Siliphos and have a leak!

The most likely cause is that the large ‘O’ ring is in the wrong position or a small piece of Siliphos is preventing the ‘O’ ring from seating correctly. (See changing the Siliphos - above).

  Product overview (English)