Osmio PRO-II-A Advanced · Compact two-stage whole-house filtration
Two-stage filtration for water throughout the home
The Osmio PRO-II-A combines a 4.5 × 10-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-A is a compact point-of-entry system for households needing broader treatment than a single sediment or carbon filter. Its two 10-inch stages retain full-flow 1-inch connections without requiring electrical power or a regeneration cycle.
- Two heavy-duty 4.5 × 10-inch antibacterial housings
- 1-inch female BSP parallel brass connections
- Useful complete-system flow stated up to 30 L/min
- 5-micron final filtration
- No electrical supply or regeneration cycle required
Two treatment stages Complementary filter media
5-micron filtration Sediment, taste and odour
Up to 30 L/min Published system guidance
Full-flow connections Female BSP brass ports
A defined two-stage sequence
Two complementary 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 × 10-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 × 10-Inch Carbon Block · 5 Micron
The final stage further reduces sediment, chlorine-related taste and odour. Published capacity is 37,000 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-A 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.
Compact full-flow installation
Two antibacterial housings with flexible mounting options
The standard side-by-side arrangement requires approximately 46 cm of height, 39 cm of width and 21 cm of depth. Where wall width is limited, Osmio advises that the housings can be mounted one above the other.
- Reinforced polypropylene heads and PET bowls
- Silver-based antimicrobial protection within the housing plastic
- EPDM bowl O-rings and pressure-release valve seals
- Maximum housing working pressure: 6 bar
- Working temperature: 4–45°C
Important: Antimicrobial housing construction protects the product material. It does not mean the system disinfects incoming water.
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 30 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 housing.
Commissioning and filter changes
Service each stage separately and protect the seals
Isolate and depressurise the system before removing a bowl. Use the supplied housing spanner carefully, then clean the bowl and inspect the O-ring before reassembly.
- Apply drinking-water-safe silicone grease to the O-ring
- Open the incoming supply slowly after servicing
- Flush through the nearest cold tap for five minutes
- Initial black carbon fines or temporary cloudiness can occur
- Inspect every joint and bowl for leaks
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 37,000 litres
fittings and O-rings
Verified technical information
Osmio PRO-II-A 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.
Continue browsing
Compare systems and plan future maintenance
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-A 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 30 L/min, not the separate 35 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 37,000 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-A is appropriately sized before ordering.