Whole-house softener ยท North Star

North Star NSC3118 31,300-Grain Water Softener

Whole-house softener

Updated October 2026

Quick verdict

A sound whole-house softener for buyers who will confirm capacity with the seller first.

Strength
20 GPM service flow.
Trade-off
Valve not named on the listing.
Right buyer
Buyers who will confirm capacity with the seller first.
Service flow (maker)
20 GPM
Material
Fiberglass, Plastic, Stainless Steel
Dimensions (seller)
1"L x 1"W x 1"H
Prices change often; the button shows today's price.

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What it does for your water

The North Star NSC3118 31,300-Grain Water Softener is a whole-house softener. Its listing gives a service flow of 20 GPM.

The listing doesn't state a grain rating or resin volume, so it can't be sized against your water from its own figures. Our sizing calculator shows what a household like yours needs.

From the listing: mounting Plumbed; power Manual/No Power; capacity stated as 31300 gallons; model NSC3118; material Fiberglass, Plastic, Stainless Steel; flow 20 GPM.

The listing gives dimensions of 1 in (L) x 1 in (W) x 1 in (H) and system in the box.

Warranty, per the listing: 1-Year Full Parts and Labor Warranty: This system comes with a full 1-year warranty on the complete unit, a 3-year warranty on the electronic control board and valve body, and a 10-year warranty on the salt storage tank and mineral tank.

Is it the right unit for your house?

Choose it when

  • Buyers who will confirm capacity with the seller first

Pass on it when

  • Sizing from the listing alone

Where it wins and where it loses

Wins

  • 20 GPM service flow

Loses

  • Valve not named on the listing
  • Needs a drain and an outlet nearby
  • Softened water carries added sodium unless you use potassium chloride

Limits to know about

  • Figures are the maker's or seller's own; check fit and capacity against your water test and your equipment's manual.

Maker's figures

Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.

Model numberNSC3118Retailer
Dimensions (seller)1"L x 1"W x 1"HRetailer
MaterialFiberglass, Plastic, Stainless SteelRetailer
Mounting / installationPlumbedRetailer
MethodIon ExchangeRetailer
Service flow (maker)20 GPMRetailer
Model nameNSC31Retailer
Warranty1-Year Full Parts and Labor Warranty: This system comes with a full 1-year warranty on the complete unit, a 3-year warranty on the electronic control board and valve body, and a 10-year warranty on the salt storage tank and mineral tank.Retailer

Units to weigh against it

Other water softeners in the catalog

Every water softeners on one grid

Final verdict

A sound whole-house softener for buyers who will confirm capacity with the seller first.

Where to buy

Our links open this exact model's product page. Prices and stock change; check what's included before you order.

Prices change often; the button shows today's price.

Each button opens this exact model. We may earn a commission on tracked links; it never changes what we publish. Disclosure

Questions buyers ask

What is the North Star NSC3118 31,300-Grain Water Softener for?
The North Star NSC3118 31,300-Grain Water Softener is a whole-house softener. Its listing gives a service flow of 20 GPM.