Hayward | W3H135FDN | Universal H-Series 135K BTU Natural Gas Pool Heater, Low NOx
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The Hayward W3H135FDN is a Universal H-Series natural gas pool and spa heater rated at 135,000 BTU. It is the compact end of the H-Series line, sized for above-ground and small in-ground pools, and built with a cupro-nickel heat exchanger and Low NOx combustion.
Features
- 135,000 BTU heating capacity for above-ground and small in-ground pools and spas
- Cupro-nickel heat exchanger resists corrosion in salt and hard water
- Low NOx design meets air quality requirements in regulated regions
- Digital LED control panel for precise temperature setting
- Polymer header and bypass valve improve hydraulic efficiency and cut pump run time
- Universal H-Series plumbing and electrical connections simplify retrofits
- Compatible with Hayward automation systems
Specifications
- Brand: Hayward
- Manufacturer part number: W3H135FDN
- Heating capacity: 135,000 BTU
- Fuel: Natural gas
- Heat exchanger: Cupro-nickel
- Series: Universal H-Series
- Emissions: Low NOx
Frequently Asked Questions
What size pool does a 135,000 BTU heater suit?
It is the smallest H-Series output and fits above-ground pools, spas, and small in-ground pools. Sizing depends on surface area, the temperature rise you want, and your climate, so have a pool professional size it for your install.
What is the difference between the W3H and W3HS series?
The W3HS models add built-in OmniX connectivity for app based control and diagnostics. The W3H models are the same Universal H-Series platform without it, controlled from the onboard panel or an external Hayward automation system.
Can this run on propane?
No. Gas type is set by model. This is the natural gas version. Order W3H135FDP if your supply is liquid propane.
Why does the cupro-nickel heat exchanger matter?
Cupro-nickel resists corrosion better than standard copper, which matters on saltwater pools, hard water, and installs where chemistry swings.
Does it work with pool automation?
Yes. It is compatible with Hayward automation systems for remote temperature control and scheduling.
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.