Hayward’s Universal H-Series 150,000 BTU Natural Gas Pool & Spa Heater provides reliable, long-lasting comfort. Built with a durable cupro nickel heat exchanger, it offers exceptional protection against corrosion and premature failure caused by unbalanced water chemistry, ensuring you get season after season of premium heating performance. The Universal H-Series boasts industry-leading hydraulic performance coupled with lightning-fast speed-to-heat capability—giving you less time to wait and more time in the water. Its low NOx emissions meet air quality standards in all low-NOx areas, so you can rest easy knowing its environmental impact is low, too.