1 / 220 Inch Big Blue Cartridge Set
The AquaGuard service, in one box.
The three 20 by 4.5 inch cartridges the AquaGuard runs on: 5 micron sediment, carbon block and 1 micron sediment. They fit any 20 inch Big Blue housing, whoever sold it. Change them every six months on municipal water, sooner on a borehole, and the showers stop noticing the filter is there.
Three stages, in this order
Housing one, 5 micron sediment. Rust, sand, mud and the visible load.
Housing two, carbon block. Chlorine and the organic compounds behind taste and smell, with its own 5 micron pass to catch carbon fines.
Housing three, 1 micron sediment. The fine particles the first two let through, and the polish a UV steriliser needs if one follows.
When to change them
When the shower pressure drops, or at six months, whichever comes first. If a gauge is fitted either side of the unit, 0.7 bar of difference with a tap running means the cartridges are full. Borehole and river water shorten the interval; a pre-filter ahead of the unit lengthens it.
Fitting, fifteen minutes
- Close the isolation valve before the unit, or the mains if there is none. Open a tap to drop the pressure.
- Press the red button on each cap to release what is left, then unscrew the bowls with the spanner. They hold three litres each; have a bucket.
- Cartridges in the order above. Check the O-rings, hand-tighten.
- Open the valve slowly, press the red buttons to bleed the air, run a tap for ten minutes. Grey water is carbon fines.
Before you buy.
Goes with it.
Whole shop
Free courierAquaGuard Whole-House Filter
Every tap, every shower, every appliance. On a stainless steel frame.
20 Inch Big Blue Carbon Block Cartridge
Housing two. Chlorine out of every shower in the house.
20 Inch Big Blue GAC Cartridge
Chlorine and smell at whole-house flow, with more contact time than a block.