Hayward Pool Heaters

(7 products)

Hayward's Universal H-Series is one of the most widely installed gas pool heater lines in the US, available in natural gas and propane configurations from 150,000 to 400,000 BTU. Built with a cupro-nickel heat exchanger, Low NOx emissions compliance, and compatibility with Hayward's OmniLogic and ProLogic automation systems, the H-Series covers everything from small residential pools to large in-ground installations. EZ Pools carries the full H-Series lineup with fast shipping from fulfillment centers in New Jersey, Colorado, and Jacksonville.

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Choosing the Right Hayward Heater Size

BTU output is the primary sizing factor for a pool heater — higher BTU means faster heat-up time and better performance in cooler climates or larger pools. As a general rule, most pool professionals size gas heaters at roughly 50,000 BTU per 10,000 gallons of pool water for a reasonable heat-up time, though climate, desired temperature rise, and whether you use a pool cover all affect the practical sizing calculation.

The Hayward H-Series comes in four BTU ratings: 150K, 200K, 250K, and 400K, each available in both natural gas (FDN suffix) and propane (FDP suffix) configurations. For a standard residential in-ground pool in the 15,000 to 25,000 gallon range in a moderate climate, the H250 is the most common choice. The H400 is better suited for larger pools, pools in colder climates, or installations where rapid heat-up is a priority — such as pools that are heated on demand rather than maintained at temperature continuously.

One important note: the natural gas and propane versions are not field-convertible between fuel types, so confirming your fuel source before ordering is critical. The model number suffix (FDN vs FDP) makes it easy to distinguish — FDN is natural gas, FDP is propane.

Hayward H-Series Features and Installation Considerations

The Universal H-Series uses a cupro-nickel heat exchanger as standard, which offers significantly better corrosion resistance than copper in saltwater pools or pools with aggressive water chemistry. This makes it a strong choice for salt chlorinated pools where heat exchanger corrosion is a common cause of premature heater failure. The H-Series also carries Low NOx certification, meeting air quality requirements in California and other states with strict emissions standards.

From an installation standpoint, the H-Series is designed for flexibility — it supports both top and side plumbing connections and is compatible with Hayward's OmniLogic, ProLogic, and AquaConnect automation platforms for remote temperature control. Minimum flow requirements vary by BTU rating, so confirming your pump's flow rate against the heater spec sheet is worth doing before installation, particularly if you're running a variable speed pump at reduced speeds.

If your existing Hayward heater needs parts rather than a full replacement, EZ Pools carries a full range of components in our pool heater parts collection including ignitors, headers, bypass valves, thermostats, and more.

Hayward H400FD Heat Exchanger Assembly - FDXLHXA1400

Frequently Asked Questions

What size Hayward pool heater do I need?
A common sizing guideline is approximately 50,000 BTU per 10,000 gallons of pool water, but climate, desired temperature rise, and pool cover usage all factor in. For a typical residential in-ground pool in the 15,000 to 25,000 gallon range, the Hayward H250 (250,000 BTU) is the most common choice. Larger pools or colder climates generally benefit from the H400.
What is the difference between the Hayward H-Series natural gas and propane models?
The natural gas models carry an FDN suffix (e.g., W3H250FDN) and the propane models carry an FDP suffix (e.g., W3H250FDP). The two versions are not field-convertible between fuel types — confirm your fuel source before ordering. Performance and BTU output are identical between the natural gas and propane versions at each size.
Is the Hayward H-Series compatible with saltwater pools?
Yes. The Universal H-Series uses a cupro-nickel heat exchanger as standard, which is significantly more resistant to corrosion from saltwater and aggressive water chemistry than standard copper heat exchangers. It is a suitable choice for salt chlorinated pools.
Does the Hayward H-Series work with pool automation systems?
Yes. The H-Series is compatible with Hayward's OmniLogic, ProLogic, and AquaConnect automation platforms, allowing for remote temperature control and scheduling. It can also be operated standalone via the onboard digital controls without an automation system.
Where can I find replacement parts for my Hayward pool heater?
EZ Pools carries replacement parts for Hayward pool heaters including ignitors, headers, bypass valves, thermostats, and more in our pool heater parts collection.

Frequently Asked Questions

What size Hayward pool heater do I need?
A common sizing guideline is approximately 50,000 BTU per 10,000 gallons of pool water, but climate, desired temperature rise, and pool cover usage all factor in. For a typical residential in-ground pool in the 15,000 to 25,000 gallon range, the Hayward H250 (250,000 BTU) is the most common choice. Larger pools or colder climates generally benefit from the H400.
What is the difference between the Hayward H-Series natural gas and propane models?
The natural gas models carry an FDN suffix (e.g., W3H250FDN) and the propane models carry an FDP suffix (e.g., W3H250FDP). The two versions are not field-convertible between fuel types — confirm your fuel source before ordering. Performance and BTU output are identical between the natural gas and propane versions at each size.
Is the Hayward H-Series compatible with saltwater pools?
Yes. The Universal H-Series uses a cupro-nickel heat exchanger as standard, which is significantly more resistant to corrosion from saltwater and aggressive water chemistry than standard copper heat exchangers. It is a suitable choice for salt chlorinated pools.
Does the Hayward H-Series work with pool automation systems?
Yes. The H-Series is compatible with Hayward's OmniLogic, ProLogic, and AquaConnect automation platforms, allowing for remote temperature control and scheduling. It can also be operated standalone via the onboard digital controls without an automation system.
Where can I find replacement parts for my Hayward pool heater?
EZ Pools carries replacement parts for Hayward pool heaters including ignitors, headers, bypass valves, thermostats, and more in our pool heater parts collection.

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EZ Pools carries the full Hayward Universal H-Series lineup in natural gas and propane configurations, with same or next-day shipping from fulfillment centers in New Jersey, Colorado, and Jacksonville.

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