Combimate

How Combimate works

Combimate is a user-friendly domestic scale prevention device that uses Siliphos, a 100% food grade material whose use is endorsed by the World Health Organisation, (FAO/WHO ref.7 and EN1208), to prevent scale build-up and corrosion in combination boilers and other domestic hot water appliances.

When in contact with water Siliphos is released in very small quantities, sufficient to keep the mineral ions in suspension. This action prevents the formation of scale while retaining the health benefits of the natural minerals contained in hard water. Siliphos coats the inside of the pipe-work, boiler heat exchanger and appliances with a non-residual, microscopic, protective coating to prevent scale-causing minerals from accumulating and aggressive soft water from corroding the system and appliances.

Installing Combimate

There are two possible installations; whole-house supply or single appliance. Whole-house supply. For this installation Combimate should be plumbed in after the stop-valve on the cold water supply to the premises. Single appliance installations - usually to protect the boiler. Combimate should be plumbed in on the cold water supply pipe. A removable divider tray reduces the amount of Siliphos required; it should be left in for single appliance installations and the Siliphos only put in the top half of the Combimate dome.

Inlet and outlet connections use 15 mm compression fittings. Vertical, horizontal and top and bottom entry pipe-work can be used which ensures easy retrofit installation. Combimate should be installed at least 0·5m from any local sources of heat such as boilers or hot water pipes.

Tried and Tested

Siliphos is a polyphosphate compound specifically developed to prevent scale build-up. Widespread use of the dosing technique over many years around the world has proved it to be reliable and effective.

Health and Safety

Siliphos is tasteless and odourless and meets the necessary WHO requirements to be classed as a 'food-grade' additive. The quantity, size and hardness of the spheres control the amount of Siliphos released. Typically this is less than 3ppm (parts per million) of phosphate in treated water and perfectly safe for human consumption.

Servicing and Maintenance

Note that Siliphos does not soften water and its effectiveness may be reduced if installed at temperatures above 80°C, in water with Carbonate hardness levels above 360ppm or at pHs below 6·5.

Combimate is manufactured to high quality standards and is WRAS approved. Over time the volume of Siliphos in the dome gradually reduces. Routine servicing is limited to ensuring that there is Siliphos in the dome. The entire Siliphos contents should be replaced at least annually, even if there are Siliphos spheres left in the dome and irrespective of their apparent condition.

Siliphos is replaced by removing the Combimate cover which is released by pressing the two red buttons on either side and pulling it forward. As the cover is released a patented integral mechanism shuts off the water supply allowing access to the Siliphos dome. The dome can then be removed from the body by undoing the red filler plug to relieve the pressure and then unscrewing the aluminium locking ring to change the Siliphos spheres.

Cistermiser replacement packs containing 800g of Siliphos, sufficient to re-fill the whole unit, complete with a new O-ring seal, are available from merchant stockists. The O-ring should be changed each time that the Siliphos is replaced.

The Combimate De-Scaling Guarantee

If Combimate is installed with a new boiler and the Siliphos replaced annually, Cistermiser guarantees that the heat exchanger will not scale up. Cistermiser will de-scale any boiler that does scale up within 3 years of Combimate installation free of charge and refund the cost of the Combimate.

  Installation information (English) [PDF Document]

  Product overview (English)