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Hayward Universal H-Series Natural Gas Heater 400K BTU 120/240V W3H400FDN
Hayward Universal H-Series Natural Gas Heater 400K BTU 120/240V W3H400FDN
A powerful and energy-efficient natural gas pool heater that delivers fast, reliable heating for pools and spas.
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The Hayward Universal H-Series Natural Gas Heater delivers powerful, energy-efficient heating, ensuring a consistently comfortable swimming experience.
Designed for durability and reliability, this 400,000 BTU heater features a robust cupro-nickel heat exchanger that withstands corrosion from saltwater and chemically treated pools.
With its universal installation flexibility, the H-Series seamlessly integrates into various pool and spa configurations, making it a preferred choice for pool service professionals.
This high-performance heater provides rapid heat-up times, allowing users to enjoy their pool without long waiting periods.
Optimized for energy efficiency, it minimizes operating costs while maintaining superior heating performance for residential and commercial pools.
Advanced safety features and user-friendly digital controls make operation simple, ensuring precise temperature management with minimal effort.

⭐⭐⭐⭐⭐
Customers praise the Hayward Universal H-Series for its fast and efficient heating capabilities.
Many users appreciate its durable construction, particularly the cupro-nickel heat exchanger that holds up well in saltwater pools.
The intuitive digital controls make temperature adjustments simple and convenient.
Reviewers also highlight the heater’s energy efficiency, noting significant savings on operating costs.
Overall, it is regarded as a reliable and high-performance pool heating solution.

- Energy Efficient: Low NOx emissions for environmentally friendly operation and cost savings.
- High Performance: 400,000 BTU heating power for fast and reliable pool heating.
- Cupro-Nickel Heat Exchanger: Provides enhanced durability against saltwater and chemical exposure.
- Versatile Installation: Universal-fit design allows seamless integration into existing plumbing setups.
- Rapid Heating: Quick heat-up times reduce waiting, ensuring immediate pool comfort.
- Digital Control Panel: User-friendly interface for precise temperature management.
- Rugged Durability: Built to withstand harsh pool environments for long-lasting performance.
- Advanced Safety Features: Includes built-in sensors for optimal safety and performance.
- Ideal for Residential and Commercial Use: Suitable for pools and spas of various sizes.

- BTU Output: 400,000
- Voltage: 120/240V
- Fuel Type: Natural Gas
- Heat Exchanger Material: Cupro-Nickel
- Emission Compliance: Low NOx
- Control Panel: Digital
- Application: In-ground pools and spas


Q: How energy-efficient is this heater?
The Hayward Universal H-Series is designed with low NOx emissions and high thermal efficiency, reducing energy consumption while maintaining powerful heating performance.
Q: Can this heater be used for saltwater pools?
Yes, it features a cupro-nickel heat exchanger, which provides excellent corrosion resistance, making it ideal for both saltwater and chemically treated pools.
Q: Is this heater easy to install?
Yes, its universal-fit design ensures compatibility with various pool plumbing setups, making installation straightforward for professionals and DIY users alike.


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Eagle Ray Digital Water Testing Kit
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