Hayward Pool Heater Universal H-Series Natural Gas Low NOx | 400k BTU
Hayward Pool Heater Universal H-Series Natural Gas Low NOx | 400k BTU - NONE is backordered and will ship as soon as it is back in stock.
The Hayward Universal H-Series Low NOx Natural Gas Pool Heater (W3H400FDN) is a 400,000 BTU high-output residential pool and spa heater designed for fast heat-up times and consistent temperature control in large inground swimming pools and spas. Engineered by Hayward, a trusted leader in pool heating, this model delivers maximum performance while meeting modern emissions standards.
With a 400K BTU heating capacity, this heater is ideal for large pools, spas, and colder climates, providing rapid recovery and reliable heating even during heavy use. The electronic ignition system ensures dependable, pilot-free startups for improved efficiency and consistent operation. A cupro-nickel heat exchanger offers superior resistance to corrosion and scale, making the heater suitable for both traditional chlorine and saltwater pool systems.
Designed to meet Low NOx emissions requirements, the Universal H-Series combines environmental responsibility with proven Hayward durability. Its robust construction and service-friendly design make the W3H400FDN a preferred choice among pool professionals for demanding residential heating applications.
Key Heater Specifications
| Specification | Details |
|---|---|
| BTU Output | 400,000 BTU |
| Fuel Type | Natural Gas |
| Ignition Type | Electronic Ignition |
| Heat Exchanger Material | Cupro-Nickel |
| Emissions Rating | Low NOx Compliant |
| Pool Type | Inground Pool & Spa |
| Application | Residential |
Alternate Part Numbers
-
H400FDN
Frequently Asked Questions (FAQs)
What size pools is the W3H400FDN best for?
This 400,000 BTU heater is best suited for large inground pools and spas, especially where fast heat-up and high demand are required.
What ignition system does this heater use?
The heater uses electronic ignition, eliminating the need for a standing pilot and improving efficiency.
Is this heater suitable for saltwater pools?
Yes. The cupro-nickel heat exchanger provides enhanced corrosion resistance, making it suitable for saltwater systems.
Does this heater meet Low NOx requirements?
Yes. The W3H400FDN is designed to comply with Low NOx emissions regulations, where required.
Is professional installation recommended?
Yes. Professional installation is strongly recommended to ensure proper gas supply, ventilation, and safe operation.
At K&J Leisure, we pride ourselves on being the best in the pool industry, not just because of our top-quality products but because of our unwavering commitment to customer satisfaction. We want you to love every purchase, but if something isn’t quite right, don’t worry—we’ve got your back!
Our Friendly Return Policy
Here’s how we make returns as refreshing as a dip in the pool:
- Hassle-Free Returns: You have a full 30 days to decide if your purchase is a perfect fit. If it’s not, simply return it—no questions asked! For purchases made in the off-season in cold weather climates, our Return window is open until June 15th! No need to wait to place an order.*
- No Restocking Fees: Unlike others, we believe in fair treatment for our customers and avoid restocking fees on the vast majority of returns. We waive restocking fees if your are not satisfied, if your problem was not resolved or if you simply change your mind!
- Wide Acceptance of Returns: Whether it’s a filter, pool cover, or accessory, we accept most items for return.
Exclusions:
- Custom orders such as Liners, Safety Covers, and Pool Kits cannot be returned, we will work with you to ensure your order is placed correctly on these non-returnable orders.
- Freight shipment orders, including heaters and larger pool filters not shipped via courier - These items may still be returned but we must recoup the original shipping cost that we have paid.
- Customer damaged - We totally understand that by the pool, exposure to chemicals, the elements and just having fun will cause some items to wear. However, we cannot accept returns if an item is damaged beyond use or in extremely poor condition.
How to make a return
Simply reach out to our friendly customer service team, and we’ll guide you through the quick and easy process. info@kjleisure.com or Toll-Free: (866)-509-8728
We can even help with return shipping options if needed!
