Hayward Universal H Series Low NOx 400,000 BTU Natural Gas Swimming Pool Heater

## Hayward Universal H-Series 400,000 BTU Natural Gas Pool Heater

The world-class thermal engineering with an Earth-friendly conscience, delivering an industry-leading **83% to 84% thermal efficiency**. Engineered with a massive 400,000 BTU output, this premium natural gas unit provides rapid speed-to-heat capabilities—capable of raising the temperature of an 800-gallon spa or plunge pool by 30°F in less than an hour. 

Its advanced low-NOx combustion design fully complies with the strictest North American air quality emission standards, making it the premier, eco-conscious heating anchor for high-end residential and commercial inground pool systems.

### Elite Architecture & Saltwater Resilience
*   **Premium Cupro-Nickel Heat Exchanger:** Factory-equipped with a robust cupro-nickel Finn Plate heat exchanger that delivers elite-tier corrosion resistance and erosion protection. It is highly resilient against aggressive water chemistry, making it fully optimized for modern salt-chlorinated pool environments.
*   **Weatherproof Forced Draft System:** Utilizes a heavy-duty combustion blower to constantly drive precise airflow through the insulated Fire Tile chamber. This completely eliminates outside environmental variables like high winds, eliminating the costly requirement of installing a separate high-wind stack.
*   **Advanced Control & Reliability:** Features an intuitive LED digital control pad that continuously monitors system performance metrics. Paired with a hot-surface electronic ignition system, it ensures reliable single-touch lighting.
*   **Universal Equipment Pad Flex:** The "universal-fit" flexible cabinet geometry simplifies installation, allowing for direct, hassle-free retrofitting alongside existing plumbing arrays and water chemistry control loops.

### Technical Specifications
*   **Product Code / SKU:** W3H400FDN *(Direct upgraded drop-in replacement for legacy model: H400FDN)*
*   **Thermal Rating:** 400,000 BTUs/hr
*   **Fuel Source:** Natural Gas (NG)
*   **Heat Exchanger Material:** Commercial-Grade Cupro-Nickel (Saltwater Optimized)
*   **Operational Altitude Rating:** Certified up to 10,000 Feet
*   **Plumbing Interface:** 2-Inch Male Threaded Connections
*   **Venting Flexibilities:** Fully certified for both Vertical and Horizontal forced vent configurations
*   **Electrical Multi-Tap:** 120V / 240V Single-Phase Adaptable Field Wiring
*   **Cabinet Physical Dimensions:** 33" Width x 39" Height x 30" Depth

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### ⚠️ Critical Compatibility & Strict Factory Warranty Guidelines
*   **Soft-Sided Pool Incompatibility Warning:** This commercial-capacity heating system **IS NOT compatible with soft-sided, vinyl-bladder, or pop-up above-ground pools** (including Intex, Coleman, or Bestway systems) due to insufficient hydraulic flow rates. Installing this equipment on any soft-sided pool infrastructure **instantly voids the product warranty**.
*   **Water Chemistry Framework:** Structural exchanger failure resulting from unbalanced pH, high saturation indices, or localized corrosive chemical spikes is explicitly excluded from standard factory coverages.
*   **Warranty Terms:** Backed by a 1-Year Manufacturer’s Limited Warranty covering factory replacement parts only. **IMPORTANT:** This factory warranty becomes strictly **void** if the mechanical gas line piping, electrical high-voltage configuration, and water plumbing loop are not completed and signed off by a **certified, licensed pool technician or professional gas fitter**.

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> 📞 **Gas Infrastructure & Logistics Coordination Inquiry:** 
> Deploying a 400,000 BTU natural gas heater requires verifying your property's gas meter capacity, line water velocity (GPM), and onsite line pressure schedules. 
> 
> Please contact our specialized equipment support team directly to confirm real-time stock availability, heavy freight liftgate delivery arrangements, or to consult on the technical accessories required for your equipment pad layout.