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Instructions for Replacing your Dental Reverse Osmosis Cartridges

Product Code: FRO-DEMIN

Before installing your new cartridges, this can be a good time to first sterlise your Reverse Osmosis system.

Installing your new cartridges

Step 1

Turn off the water supply to the unit using the Inline shut off valve attached to the blue tubing or the saddle clamp attached to the copper pipe. (Turn the T bar tap on the saddle clamp clockwise until it stops turning.)

On the TOP of storage tank, turn the tap to the closed position (ie so the blue lever is at right angles).

Open your sink top Tap / faucet



(These are the two filters on top of the unit ie Filter 1 and Filter 2) in image 1 above. (Please note your two new post filters will look identical)

Remove the small pipe AND elbows section that joins the two filters by depressing the small “collet rings” where the elbow stems join the filter. (You push these “collet rings”  IN whilst pulling the elbows OUT. (If relevant) first remove the blue collect ring lock from the push fit connectors on inlet/outlet.

Install new post filters – exchanging like for like - ensuring correct direction of flow. (Note the way the ends “D” fit compared with the membrane at “D1”)

Filter 1 inlet comes from Filter 2. The outlet goes to your sink top Tap / faucet 

Filter 2 inlet connects to the T piece and outlet connects to Filter 1

Replace the pipe AND elbows section. It's a simple push-fit action. Tug to check they are securely in


(These are Filters 3 and 4 that sit in the white cylinders underneath the unit. They look identical).

Place a drip tray beneath the system to catch any water.

Unscrew the housings that sit under the main unit by turning to the left (Use the special spanner if available - or you could use an oil-filter type spanner. Do NOT use the in/out ports as leverage or you might weaken and break them).

Remove the old filters and discard.

Place the new filters into the housing and close them again.  DO NOT OVERTIGHTEN.

TIP: Add a few dabs of vaseline to the screwthreads to make it easier to open next time


Now reverse Step 1 above to turn the system on.  Check for any small leaks

Let the tank fill up fully. Restart the system and empty the first two tank fulls of water to remove any carbon fines / carbon dust.

VIDEO Instructions are also available please see

Any Problems? Please Telephone 020 8761 6611

Important Note re Reminders

To avoid long term bacteria build-up it is important to change or disconnect your water filter on time.

We will email you reminders when it's to change, but please make sure you whitelist our email address so these reminders aren't sent to spam.

And/ or set an alarm now on your mobile or use Siri etc

Please note your feedback and any suggestions as to how we can improve our service are always appreciated.


Thank you

Sales Admin Team
Telephone 020 8761 6611

Water Filter instructions / Guides for fitting and installing


Need advice?
Please call us on
020 8761 6611


UK Water Filters Ltd
Unit D120
Parkhall Industrial Centre
SE21 8DE

UK Water Filters Ltd a Company Limited by Guarantee,
Registered in England,
Company Number: 05249436,
VAT Reg. No. 863 7634 91


Questions? Call us for friendly advice
+44 (0) 20 8761 6611




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