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ScaleCutter 3/4 in. Water Softener for Rinnai Tankless Water Heaters and Combi Boilers

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  • Ideal for Sensei SE+ tankless water heaters and M-series boilers
  • Helps prevent lime-scale buildup and corrosion
  • Made from premium quality plastic for durability
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Frequently Bought Together


Product Overview

The Rinnai scale cutter can be used with Tankless Water Heaters and Combi Boilers. It works by simply preventing the amount of minerals found in potable water to prevent lime-scale buildup and corrosion that can diminish hot water performance within the appliance. The Scale Cutter offers similar benefits of traditional water softeners.
  • Scale cutter system unit 3/4 in. water conditioning system
  • For use with Rinnai Tankless water heaters
  • Dimensions: 5.18 in. x 13.34 in. x 4.78 in.
  • Water heater accessory
  • Country of origin: United States
  • For use with SENSEI SE+ tankless water heaters (condensing) and m-series boilers
  • Amber finish
  • Package quantity 1
  • Plastic construction
  • 1 year limited warranty
  • *Note. Rinnai is changing the language in its warranty terms and conditions found in the current User Installation manuals. The existing statement will be replaced by the following: "This Limited Warranty applies only to products that are installed in the United States and Canada. Improper installation may void this Limited Warranty. It is recommended that a trained and qualified professional who has attended a Rinnai installation training class complete your installation." All warranties (old or new manual) will be honored as written above.

  • California residents

Info & Guides

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Product Depth (in.)
Product Height (in.)
Product Width (in.)


Compatible Brand/Model
Finish Family
Bronze/Copper Metallic
For Use With
Gas Tankless
Pack Size
Product Type
Supply Line Softener
Product Weight (lb.)

Warranty / Certifications

Manufacturer Warranty
1 Year limited warranty

Questions & Answers

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Customer Reviews

  • 4.8
    out of 4 reviews
  • 100% recommend this product
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Showing 1-4 of 4 reviews
by HomeDepotCustomer
    by BigDuke6
    • Verified Purchase
    1 person found this helpful
    by HARRY
    • Verified Purchase
    If you read the installation and warranty for the Rinnai on-demand hot water heater, this is requ...
    If you read the installation and warranty for the Rinnai on-demand hot water heater, this is required for hard water sites. The warranty is void for damage caused by unfiltered hard water. The distributor / installer claimed to have no idea what I was talking about, leading me to suspect that he was just setting up his customers for downstream repair work or unit replacements, which for him would be far more profitable than installing a filter. I bought this on my own and had it installed; whether it works satisfactory or not won't become evident for at least 6 months, but at least my new hot water system now conforms to the warranty requirements. Only drawback is that it should not be in direct sunlight (which is not in the specifications but only disclosed in the installation package), so I had to revise installation worksite to accommodate that requirement. It's been installed and working for about one month.
    by JAMES
    • Verified Purchase
    • Recommended Product
    2 people found this helpful
    Showing 1-4 of 4 reviews