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Rhombus Dental Reverse Osmosis System

by Rhombus
Original price £389.95 - Original price £389.95
Original price
£389.95 - £389.95
Current price £389.95

The best-selling Rhombus system is a complete reverse osmosis system, designed specifically for the busy dentist which, with 3 stages of filtration, will remove up to 99.9% of impurities from tap water and potentially get your TDS value down to zero.

This system is a great economical choice to produce distilled quality water for use on Autoclaves.

R.O has big advantages on Distillers.

  • Regularly heating water to boiling point can require large amounts of electrical energy: distillers can use more than 600 watts of energy to produce one litre of water, approx. £300 per year in electricity alone.
  • Heating elements and can be prone to scale damage and can fail. Many distillers last only 2 to 3 years.

R.O has big advantages on Bottled Water.

  • Some surgeries can buy in between 10 - 20 litres of de-ionised water per day.
  • For a small, two surgery practice this equates to over £600 per year. For a larger practice, it will be much more.
  • Water is heavy and transporting it is costly and is not good for the environment.

Due to the specialised filters and monitor, the Rhombus R.O cannot be compared directly with regular R.O units available on the web. This unit, tailored for the dental sector and for autoclave water production features a post membrane demineralisation cartridge and integral TDS conductivity monitor to ensure consistent production of quality water.


* Premium water filters and membrane.

* High Performance TDS Monitor to ensure quality water is being produced.

* A mains pressure meter.

* A heavy duty faucet tap ( new for 2018).

* Free Technical assistance if needed ( Mon-Thur 8.30am-17.30pm) Friday 8.30am - 17.00.

The Rhombus Dental R.O meets the full legislative standards in respect of water used.

Please note any R.O system will only function correctly if your mains water pressure is good. Over 2.7 bar mains pressure is recommended for the system to function at high performance. If you have poor water pressure a booster pump is available. Please call us on 01704 531556 if you have any questions in relation to this product.

We have been supplying Rhombus equipment for over 15 years and are extremely knowledgeable on the system and Reverse Osmosis as a whole. Our dedicated sales staff are all fully trained on the system and can give advice on installation and changing of consumables.

We have included a Questions and Answers sheet to help you understand the product in depth but if you want any questions answering you can always call us on 01704 531556.

Main Module

Height                    430mm

Height                     420mm

Width                     395mm

Diameter                  280mm

Depth                     143mm

Capacity (max)          9 litre



Below is a list of questions that we are frequently asked by prospective and existing customers that we hope will be of use to you.

What is it?
The RHOMBUS is the result of product development in conjunction with feedback from distiller users who are looking for better suited ways of ensuring an adequate supply of purified water for use in autoclaves & washer/disinfectors. Based on standard Reverse Osmosis systems which remove up to 98% of impurities, the RHOMBUS takes this process one step further and removes 100% of impurities from UK mains water.

Is it easy to install?
In a nutshell – yes. The RHOMBUS arrives pretty much assembled and ready to install with minor attention required and some basic DIY actions, leaving you ready to use the system. If the user is not confident to carry out minor/basic DIY they should consult a suitably qualified handyman/plumber.

Does it use electricity or chemicals?
Another short answer – No. The system works off of the incoming mains water pressure and knows when to purify water and when to stop. The only power used by the system is in the integral TDS meters, and these are generally 2 x AA batteries with a life span expected to be at least 14 months on normal use.

Is it a complicated process?
Although Reverse Osmosis can be tricky to explain if the user is not familiar with technical jargon, it is a simple process to understand. The incoming water goes through 3 stages of filtration – which requires no actions on the part of the user. Install it – give it time to fill up – and then you will have purified water. Using water pressure only, the system rejects impure water to drain, whilst storing purified water for use.

Does it require technical knowledge for maintenance?
Again the RHOMBUS leaves us with a short answer – No. When you need to change the first filter (every 6 months at least), you isolate the supply to the system, close the tank, press the tap and wait a few seconds. Then you open the filter housing and change the internal cartridge. The same process is used on the membrane – but this is done every 2/3 years and the post cartridge is done every 2 to 3 months depending on use.

Is changing the filters hard to do?
Whilst it may seem daunting to carry out a filter change for the first time, there is practically nothing that can go wrong. The most common mistake is people forget to re-open a valve when the change is complete. So after one or two changes, you would soon know the difference between a shut off valve and a flow restrictor.

Is it expensive to run?
The average annual running cost of a RHOMBUS system over a 3 year period is on average between £65 and £95.00 depending on filter change frequency. Compared to a water distiller this is a huge saving as more water is available on tap and no power is consumed during purification.

How will I know to change the filters?
If you remember that the pre filter (carbon block) must be changed at least every 6 months and the membrane should be changed at least every 3 years, then the system will do the rest. The integral TDS meters tell you how the system is performing and when the read out on the final meter is above 000ppm – change the post cartridge.

What are the 3 stages of filtration & purification?
The first filter (carbon block) is designed to remove taste/odour inducing chemicals that can damage the membrane and affect the performance of the whole system. This stage will remove particles down to 20microns, ensuring that the membrane is not blinded by contaminants or damaged by chemicals. The membrane will purify water down to 0.0009 microns, and the purified water goes to the storage tank whilst the impure water gets flushed to drain. When you open the faucet, the water then goes through the final stage of filtration – a bed of demineralising media where residual impurities are removed by the special mixed media. The membrane will remove up to 98% of impurities and providing correct monitoring of the system and TDS meters, any impurities that get through the membrane will not make it past the final stage of filtration.