The A. O. Smith HomeShield AOS-HS-1200 is a point-of-entry whole-house water filter for cold water service. It treats the incoming supply for the whole building through a single mineral tank charged with 2.5 cubic feet of a patent-pending media blend, and it operates without a drain line and without a wastewater discharge. The system comprises the mineral tank, an In/Out Head with a bypass valve, and a Performance Indication Device.
The system conforms to NSF/ANSI 53 for its PFAS reduction claims, and is tested and certified by WQA to NSF/ANSI Standard 53 and CSA B483.1 for the claims specified on its Performance Data Sheet. Certified PFAS claims cover PFOA/PFOS, PFHpA, PFHxS, and PFNA, each reduced by more than 99.9 percent, over a rated capacity of 500,000 gallons at the rated service flow of 5.7 gpm. The manufacturer also reports chlorine and chloramine reduction over the same 500,000-gallon capacity; those two claims are internally validated and are not certified by WQA.
Water enters and leaves the In/Out Head through 1-inch NPT connections. Anti-channeling plates distribute flow across the media bed. The Performance Indication Device installs in the outlet plumbing, runs on a 12 V supply from a transformer connected to a dedicated grounded 115V/60Hz outlet, and reports remaining capacity on a color-coded LCD touchscreen so the owner knows when the tank is due for replacement. At the end of rated capacity, or on any service requiring replacement of the mineral tank, its internal contents, the reducer bushing, or the In/Out Head, the entire water treatment device is replaced rather than recharged.
The unit requires a pre-filter rated at 5 microns or lower installed immediately upstream. A cartridge filter may be installed downstream as a polishing filter. Influent water must meet the quality requirements stated on the Performance Data Sheet, including pH of 7 to 8, total hardness under 10 gpg as CaCO3, iron under 0.3 ppm, manganese under 0.05 ppm, and turbidity under 1 NTU. The system must not be used with water that is microbiologically unsafe or of unknown quality without adequate disinfection before or after the system.
