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OneFlow® Model OFTWH Anti-Scale System
The Intelligent Scale Solution™ for Tankless Water Heaters
Tankless water heaters with their tightly packed, small gauge tubing are prone to the overheating and malfunction that result from scale formation.
Today there's a solution to this problem – OneFlow® Model OFTWH. The same water treatment technology that’s been used successfully in commercial plumbing is now designed to ensure scale-free tankless heater operation in your home or small business.
Benefits
- Compatible with all major tankless water heater brands
- Maintains manufacturer's stated water heater efficiency
- Works to prevent heater malfunction due to scale build-up
- Diminishes existing scale problems and costs associated with de-scaling
- Environmentally friendly alternative to water softeners
- Designed for tankless water heaters up to 10 gallons per minute
- Virtually maintenance free - no salt or chemicals to add or maintain
- No Electricity or backwashing required
- Simple sizing & installation with standard ¾ in. connections and included mounting bracket
- Inlet ball valve and filter wrench for easy shutoff and filter changes
- Long lasting OneFlow® cartridge – change once every two years
A Breeding Ground for Scale

Hard scale can accumulate over time on pipes, valves, fixtures and heating elements. Heat increases the tendency for limescale deposits to form; the higher the heat the greater the buildup. Tankless hot water heaters, designed to operate at high efficiency, can be a breeding ground for scale. Once formed, these scale deposits result in malfunctions and calls for service.
Single Cartridge; Easily Installed
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The OneFlow® Anti-Scale System provides protection from scale formation on internal and external plumbing surfaces. The OneFlow® Model OFTWH is a single cartridge-based system that is easily installed on a cold water line prior to a tankless water heater. Once installed, the system requires very little maintenance, no backwash, no salt and no electricity. It is truly The Intelligent Scale Solution™.
Visit TheScaleSolution.com
To learn more about OneFlow® anti-scale technology and how it can solve your scale problems, visit TheScaleSolution.com or contact your Watts representative.
Pressure – Temperature
- Maximum Pressure: 90psi/620.1 kPa
- Maximum Temperature: 100ºF/38ºC
- Minimum Temperature: 35ºF/2ºC
Inlet/Outlet Connections
- ¾ in. FNPT
Service Flow Rate
- 0.5 gpm to 10 gpm (1.9 Ipm to 38 Ipm)
Gallon Rating:
- OFTWH: up to 6 gpm, 24/7/365 for 2 years for the OFTWHRM.
Videos
- Model OFTWH Introduction Video
Model OFTWH Intoduction
- OneFlow® Anti-Scale System Video
OneFlow® Anti-Scale System
Additional Info
How to Buy
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