Here to help : 01352 838281

Doby OneFlow Water Filter Cartridge

Replacement water filter cartridge for our Doby OneFlow mains hard water filter.



Product SKU: OF140RC



An environmentally friendly solution for preventing scale build up. 

The most effective salt-free scale prevention technology there is. 

The perfect hard water filter cartridge for residential systems. 

Fits our Doby housing.

If your water is harder than 25 grains (427 ppm CaCO3) then OneFlow may not be suitable for you. Check with your local water supplier who will be able to tell you what the hardness measurement is. 

Please note that a TDS meter may give you a higher reading but it's measuring all total dissolved solids and not just CaCO3. This is another reason to contact your local water supplier.

Cartridge details:

  • Watts One Flow OF140RM
  • 4.5" x 20"
  • Up to 4.0gpm with a working life of approximately 24 months
  • Certified NSF/ANSI standard 42 NSF
  • Certified by ISO 9001
  • Performance tested and verified by independent laboratory testing.

Why do I need to change the o-ring?

You can tell if the seals start leaking, which is obvious, I know.

Even if there are no leaks you may find that the profile of the O ring becomes flattened because of prolonged time under compression. The cross section should be round and if it's not it may not seal easily.

However, we recommend that you replace the O rings every two or three years as a precautionary measure.

One of the main reasons for changing O rings periodically is that as they age and compress, the housing bowl needs to be tightened excessively. That leads to difficulty loosening the bowl from the cap next time the cartridge needs to be replaced.

To help prevent automated spam, please answer the following question.

Complete the following: Fish and  

Related Items

  • Doby OneFlow Hard Water Filter

    SKU: DOFA8210

    Doby OneFlow Hard Water Filter

    Are you frustrated by your very hard water? With our Doby OneFlow hard water filter you can effectively remove limescale from your water. Call us on 01352838281.



This is the basket Message

This is the basket Message