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Hayward Universal H-Series H400 Low NOx Pool Heater, 400,000 BTU, Natural Gas

Only
$4,499.00

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Only
$4,499.00

In stock

Brand
Hayward
MPN
H400FDN Replaced by W3H400FDN
SKU
4076

Item 4074P

Product Options:

Only
$4,499.00
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Pool Supplies Fast Pool Supplies Fast Next Day Delivery
Next Day Delivery Next Day Delivery info
This item will arrive on the next business day for orders placed by 3:00 PM with the exception of 2:30 PM for the Texas warehouse.
Ground Delivery Ground
Your current location is outside the Next Day Delivery area. This item ships FedEx Ground and usually arrives in 2 to 3 business days.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Freight Delivery Freight Delivery info
This item ships FREE freight and usually arrives in 5 to 7 business days. Optional Lift Gate service available for $29.99. Refusing delivery of non-damaged shipments will result in extra fees.
Product Overview
  • 1 year warranty.
  • Hayward H-series Pool Heater provides an energy-efficient and environmentally responsible low NOx performance solution for pools and spas!
  • Cupronickel Heat Exchanger with Totally Managed Flow provides exceptional corrosion resistance and erosion protection.
  • Exclusive silicon nitride ignition system provides dependable lighting and reliable operation
  • Ideal for salt chlorinated filtration systems
  • Choice of left-side or right-side electric, gas and water connections for ultimate flexibility
  • Totally Managed Flow provides exceptional corrosion resistance and erosion protection.
  • Ideal for salt chlorinated filtration systems
  • Hayward Gas Pool Heaters provides superior hydraulic performance

Product Description

Hayward Universal H-Series Low NOx Pool Heaters

Enjoy energy-efficient and environmentally responsible heating with Hayward’s Universal H-Series Low NOx Pool Heaters. Designed for both in-ground and large above-ground pools, these heaters deliver reliable, high-performance heating with advanced low-emission technology. Whether you're upgrading existing equipment or installing new, the Universal H-Series adapts easily to your setup.

Each model features a durable cupronickel heat exchanger with Totally Managed Flow for superior protection against corrosion and erosion—perfect for use with modern salt-based chlorination systems. The silicon nitride ignition system ensures fast, dependable start-ups every time. Built with efficiency, durability, and ease of use in mind, the H-Series is a trusted choice for pool owners seeking consistent heating performance.

Key Features:

  • Low NOx emissions—ideal for environmentally conscious pool owners
  • Efficient heating for in-ground and large above-ground pools and spas
  • Cupronickel heat exchanger resists corrosion from saltwater systems
  • Advanced ignition system for reliable lighting
  • Compatible with new or existing pool equipment
  • Available in 150K, 200K, 250K, and 400K BTU models

Note: For elevations above 6,000 ft, please request a high-altitude compatible model.

Click here for freight delivery details

H-Series Size Chart

ModelRecommended Pool Surface Area
H150450 sq ft
H200600 sq ft
H250750 sq ft
H4001400 sq ft

For technical support, contact Hayward at 1-800-HAYWARD or visit www.hayward-pool.com.

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Specifications

Frequently Asked Questions

What size propane or gas pool heater do I need for my pool?

One formula commonly used to calculate propane/gas heater BTU requirements is the following: BTU = (surface area/3) x 100. For an easy estimate, use our pool heater BTU calculator located on our pool heaters page.

What's the difference between a gas heater and a heat pump?

Gas heaters (propane or natural gas) heat pool water quickly and can work in any climate. Heat pumps are energy efficient and better suited for regular heating in warmer environments, though they work more slowly because they use outdoor ambient temperature and the heat generated from the pump to heat the pool.

How long does it take for a gas pool heater to heat a pool?

Heating time depends on your pool’s size, heater type, and outside temperature. On average, gas or propane heaters are fast and can raise the temperature by 1–3°F per hour.

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