Osmio PRO-II-XL Advanced · High-flow two-stage filtration
Whole-house filtration for larger homes and higher water demand
The Osmio PRO-II-XL combines a 4.5 × 20-inch Active Ceramics filter with a 5-micron carbon block. Installed on the incoming cold main, it targets sediment, chlorine-related taste and odour before water is distributed to taps, showers and appliances.
Point-of-entry treatment
Filter the mains supply before it travels around the property
The PRO-II-XL is designed for properties that need more flow than the standard 10-inch PRO-II-A system. Its larger 20-inch cartridges provide greater media volume while retaining full-flow 1-inch connections.
- Two heavy-duty 4.5 × 20-inch antibacterial housings
- 1-inch female BSP parallel brass connections
- Useful complete-system flow stated up to 40 L/min
- 5-micron final filtration
- No electrical supply or regeneration cycle required
Two treatment stagesComplementary filter media
5-micron filtrationSediment, taste and odour
Up to 40 L/minPublished system guidance
Full-flow connectionsFemale BSP brass ports
A defined two-stage sequence
Two large-format filters with separate service lives
Water passes through the Active Ceramics cartridge first and the carbon block second. Each filter must be monitored and replaced according to its own time or capacity limit.
4.5 × 20-Inch Active Ceramics Filter
A patented blend of four active ceramic media, with each element performing a different treatment function. Published service life is 1–3 years or up to 300,000 litres, depending on incoming water quality and usage.
4.5 × 20-Inch Carbon Block · 5 Micron
The final stage further reduces sediment, chlorine-related taste and odour. Published capacity is 48,000 litres, with replacement recommended every 6–12 months or sooner when conditions require.
Important: Published capacities are guidance rather than a guaranteed service life. Higher contaminant levels, heavier use and declining flow can require earlier replacement.
Choose it for the correct purpose
Whole-house filtration does not soften hard water
The PRO-II-XL is intended for sediment, chlorine-related taste and odour filtration. It does not remove the dissolved calcium and magnesium that cause hard-water scale.
Whole-home filtration
Treats the supply before distribution around the property.
Can complement a softener
Filtration and softening can work together because their roles differ.
Not limescale removal
Choose a water softener when hardness reduction is the priority.
Plan before ordering
Installation requirements that affect flow and reliability
This system becomes part of the main plumbing. Incoming pressure, peak demand, pipe size, wall strength, bypass design and servicing space must be confirmed before installation.
Measure peak flow
Confirm the property’s actual peak demand. The stated 40 L/min is complete-system guidance, not a guarantee for every installation.
Test the pressure
Measure incoming pressure before installation. Osmio recommends a pressure-reducing valve when the measured pressure exceeds 5 bar.
Provide a bypass
A three-valve bypass is recommended so water service can continue while the system is isolated for maintenance.
Allow servicing space
Leave at least 2 inches below each bowl and adequate working space for safely removing a water-filled 20-inch housing.
Commissioning and ongoing care
Flush slowly, record usage and inspect the seals
After installation or a cartridge change, fill the system slowly and flush through the nearest cold tap for five minutes. Inspect for leaks after commissioning and check the housings, fittings and O-rings at least every six months.
or 300,000 litres
or 48,000 litres
fittings and O-rings
Verified technical information
Osmio PRO-II-XL Advanced specification
Installation information
Read the manual before arranging the plumbing
The guide covers pressure checks, bypass planning, filter order, mounting, O-ring preparation, commissioning and cartridge replacement.
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Helpful answers
Frequently asked questions
What is the difference between PRO-II-A and PRO-II-XL?
The PRO-II-A uses 4.5 × 10-inch cartridges and is listed for useful flow up to 30 L/min. The PRO-II-XL uses larger 4.5 × 20-inch cartridges and is listed for useful flow up to 40 L/min.
Will the PRO-II-XL remove limescale?
No. It is a filtration system rather than an ion-exchange water softener, so it does not remove the dissolved calcium and magnesium that cause hard-water scale.
What flow rate should be used when sizing it?
Use the complete-system guidance of up to 40 L/min, not the separate 70 L/min maximum rating of an empty individual housing. Cartridge condition, incoming pressure, pipework and peak demand all affect the flow available in practice.
How often are the filters replaced?
The Active Ceramics filter is listed for 1–3 years or 300,000 litres. The carbon block is listed for 6–12 months or 48,000 litres. Replace either cartridge sooner if water quality or declining flow requires it.
Does the antibacterial housing disinfect the water?
No. The silver-based antimicrobial additive protects the housing material. It is not a substitute for UV treatment or another validated microbiological barrier.
Should a bypass be installed?
Yes, Osmio recommends a three-valve bypass where space permits. This allows the filter to be isolated for maintenance while retaining a route for water service.
Can the system be installed outside?
The manual permits an external installation only when the system and pipework are properly boxed, weatherproofed and protected from freezing. A suitable frost-protected internal location is preferable.
Premium product support
Need to confirm the flow, pressure or installation space?
Send us the incoming pipe size, measured pressure and flow, property size and available installation dimensions. We will help determine whether the PRO-II-XL is appropriately sized before ordering.