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AO Smith

A.O. Smith ProMax 34,000 Grain Water Softener

Model AO-WH-STG-200
4.3/5 from 312 ratings
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Warranty
10 years tanks, 5 years valve
Flow Rate
9 GPM service
Brine Tank
150 lb salt capacity
Dimensions
9" x 48" mineral tank
Connections
3/4" or 1" NPT
Iron Removal
Up to 2 PPM clear water iron

A.O. Smith ProMax 34,000 Grain Water Softener Review

The A.O. Smith ProMax AO-WH-STG-200 is a 34,000-grain demand-initiated water softener engineered by the same brand that produces the ProLine water heaters most commonly paired with softened water supply lines. The ProMax uses ClearShield resin protection technology, which applies a corrosion-resistant coating on the resin bed to slow degradation from chlorine exposure in municipal water. This extends resin service life in high-chlorine water supplies compared to standard uncoated resin. The system includes a Fleck-style demand control valve, a 150-lb brine tank, and a 3-valve bypass assembly. Dimensions are compact at 9 x 48 inches for the mineral tank, allowing installation in tight utility closet spaces. A.O. Smith backs the ProMax with a 10-year tank warranty and 5-year valve warranty.
Pros
  • ClearShield resin resists chlorine degradation longer than standard resin
  • Compact 9-inch tank diameter fits narrow spaces
  • A.O. Smith brand warranty and support network
  • NSF 44 certified
Cons
  • 34,000 grains is on the lower end for families of 4 in hard water areas
  • Iron removal limited to 2 PPM

Full Specifications

Brand
AO Smith
Model Number
AO-WH-STG-200
Warranty
10 years tanks, 5 years valve
Flow Rate
9 GPM service
Brine Tank
150 lb salt capacity
Dimensions
9" x 48" mineral tank
Connections
3/4" or 1" NPT
Iron Removal
Up to 2 PPM clear water iron
Resin Volume
1.0 cubic feet
Certifications
NSF/ANSI 44
Grain Capacity
34,000 grains
Resin Technology
ClearShield chlorine-resistant coating

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