Hayward | W3HS400FDN | Universal H-Series 400K BTU Natural Gas Heater with OmniX
Couldn't load pickup availability
The Hayward W3HS400FDN is a Universal H-Series natural gas pool and spa heater rated at 400,000 BTU, the highest output in the series. It includes OmniX connectivity for app based control, scheduling, and diagnostics, and uses a cupronickel heat exchanger for durability in salt and hard water conditions.
Features
- 400,000 BTU heating capacity for large in-ground pools and pool and spa combinations
- OmniX connectivity for scheduling, diagnostics, and remote access with a compatible gateway
- Cupronickel heat exchanger resists corrosion in salt and chemically aggressive water
- Low NOx design meets air quality requirements in regulated regions
- Digital control panel for precise temperature setting
- Universal H-Series plumbing and electrical connections simplify retrofit installs
- Fast temperature recovery for spas and frequently used pools
Specifications
- Brand: Hayward
- Manufacturer part number: W3HS400FDN
- Heating capacity: 400,000 BTU
- Fuel: Natural gas
- Heat exchanger: Cupronickel
- Series: Universal H-Series with OmniX
- Application: Large in-ground pools and spas
Frequently Asked Questions
What size pool does a 400,000 BTU heater suit?
It is the top output in the series and suits large in-ground pools and pool and spa combinations that need fast recovery. Correct sizing depends on surface area, the temperature rise you want, and your climate, so have a pool professional size it for your install.
What does OmniX add?
OmniX is Hayward's built-in connectivity platform. Paired with a compatible gateway, it allows app based temperature control, scheduling, and remote diagnostics instead of walking out to the pad.
Can this run on propane?
No. Gas type is set by model. This is the natural gas version. Order W3HS400FDP if your supply is liquid propane.
Why does the cupronickel heat exchanger matter?
Cupronickel resists corrosion better than standard copper, which matters on saltwater pools, hard water, and installations where chemistry swings.
How is the W3HS series different from the older W3H series?
The W3HS models carry OmniX connectivity built in. The W3H models are the same Universal H-Series platform without it.
Can I install it myself?
Gas heater installation involves gas piping, venting, and electrical work, and most jurisdictions require a licensed installer. Improper installation can also affect warranty coverage.
Sold by AppaeTech Pool Supply, an authorized Hayward reseller.