10 Best Gas Pool Heaters 2025 in the United States

The Hayward W3H400FDN Universal H-Series gas pool heater is designed for in-ground pools and spas, boasting a strong BTU output of 400,000, making it suitable for larger pools that require quick heating. One of its main strengths is the durable cupro nickel heat exchanger, which is resistant to corrosion, helping it last longer even in challenging water conditions. Additionally, its efficient hydraulic design reduces the need for long circulation pump run times, saving you money on energy bills.

Operating the heater is made easy with a front-panel access and an intuitive control pad, which is perfect for those not familiar with complex setups. Plus, it meets low NOx emission standards, contributing positively to the environment, which is an important feature for many users today.

However, the heater is quite heavy at 195 pounds, which could complicate installation if you’re not prepared. Lastly, be mindful of the size (39.6 x 32.8 x 30.6 inches) as it may require a significant amount of space. If you are looking for a reliable and efficient heater for a larger in-ground pool or spa, the Hayward W3H400FDN presents a solid option, but keep in mind the installation challenges and the need for adequate space.

The Raypak Digital Cupro-Nickel Natural Gas Pool Heater delivers strong heating power with a 240,000 BTU output, making it suitable for medium to large pools and spas. It uses natural gas, which is commonly available and often cost-effective. The unit features a microprocessor-controlled thermostat, allowing precise temperature control and remote compatibility for convenience.

Its pagoda-style design helps it withstand harsh weather, and the powder-coated galvanized metal construction suggests good durability and resistance to rust or wear. Weighing 213 pounds and measuring 28 x 23 x 38 inches, it is a sizable unit that requires professional installation to fit properly in your pool equipment area. The use of cupro-nickel heat exchangers typically indicates better corrosion resistance, which is a plus for longevity, especially in outdoor pool environments.

This heater is well suited for pool owners seeking reliable, straightforward natural gas heating with durable build quality and decent control features. However, those needing the highest efficiency or compact size might want to explore other options.

The Raypak 406,000 BTU Digital Natural Gas Pool Heater is designed for pool owners looking for efficient heating solutions. One of its significant strengths is its impressive BTU output, which makes it suitable for larger pools or spas, ensuring water reaches a comfortable temperature quickly. The cupro-nickel construction offers excellent durability, especially in harsh weather conditions, making it a reliable choice for those in varying climates. The pagoda design helps protect the unit from the elements, enhancing its longevity.

In terms of efficiency, this heater uses natural gas, which is often more cost-effective compared to propane. The microprocessor-controlled thermostat is another valuable feature, allowing for precise temperature control, which can lead to energy savings and more comfortable swimming conditions.

However, there are some drawbacks to consider. Weighing in at 249 pounds and with dimensions of 44 x 34 x 31 inches, this heater is relatively large and heavy, which could pose challenges during installation. Prospective buyers should ensure they have enough space and the proper setup for installation. This product is best suited for pool owners looking for a powerful and durable heater, but it would be wise to consider space and installation requirements before deciding.