Hayward CSPAXI11 Review & Rating

  • Hayward CSPAXI11 Electric Spa Heater Review
9.1 score
[Editors rating (9.1)] = ContractorCulture score (9.1)/10

Editor rating: 9.1 / 10
User's rating: based on 0 user ratings
1 star
2 star
3 star
4 star
5 star
Add your Rating

Very durable

Safety sensor against all risks

Does not emit environmentally unfriendly gasses


Good for smaller pools

Hayward CSPAXI11 Review

As an electric resistance heater, the Hayward CSPAXI11 generates heat by applying an electrical current to a heating element, which is known as a resister, inside of the pool heater. As electricity heats up the resister, water is passed over the resister and heated before exiting into your pool. The simple process continues until your pool reaches your desired temp. When not in use, the resister cools back down until you flip the switch and crank up the currents again.

With a high-quality 304 stainless steel tank, heating element, and threaded head, this little engine that could is highly corrosion-resistant and guaranteed to perform for years.

When you factor in its advanced safety sensor, useful indicator light, service-ease design, and surprisingly low price tag as well, it’s easy to see why the Hayward CSPAXI11 is one of the most popular spa and small pool heaters being made today.

Installing It

Producing 11 kilowatts and 240 volts, the Hayward CSPAXI11 pulls approximately 45 amps, which means you’ll need at least a 50-amp wire and a 40-amp breaker in order to operate it. If you opt for the cheaper route and choose a wire not designed for the current produced by the heater, it may overheat, melt the insulation, and potentially fail or cause a fire. Since it’s an electric heater, there are no gas lines or connections to worry about. Once you have the right wiring and breaker, actually installing the heater and firing it up is rather simple.

Using It

In addition to being easy to install, this affordable spa heater is refreshingly easy to use as well. If you have a 3/4 pump, you simply need to flip the switch to fire it right up and begin heating you pool or spa. If you have a bigger pump, however, the reset button on the back of the heater may pop when the heater stops or the heater may not turn on like it should when the pump starts. If this happens, you’ll need to adjust the water pressure valve located inside of the heater until it works correctly.

Best Uses for the Hayward CSPAXI11 11-Kilowatt Pool Heater

The Hayward CSPAXI11 is a compact electric resistance heater designed for spas and small pools. That being said, it’s important to note that it doesn’t provide instant heat. In fact, if you have a 1,000-gallon spa, it will heat it by five degrees per hour. Thus, if the water in your spa is 75 degrees, it will take five hours to heat it up to a steaming 100 F. If you have a larger above ground pool, you can expect it to take your pool water from 70 F to 80 F in approximately four hours, which is pretty impressive for such an inexpensive little heater.

Final Words

The Hayward CSPAXI11 may not be large enough or powerful enough to heat up an Olympic-size pool, but if you’re in the market for an efficient, reliable, and cost-effective heater for a spa or small pool, this mighty little heater is hard to ignore. With low operating costs and an even lower price tag, the Hayward CSPAXI11 is tough to beat.


With this simple operating procedure and Hayward’s long history as a premier pool heater manufacturer, the Hayward CSPAXI11 11-Kilowatt Electric Spa Heater is super reliable.

304 Stainless Steel Tank – Constructed out of top-quality 304 stainless steel, the tank is incredibly corrosion-resistant and built to last for years.

304 Stainless Steel Heating Element and Threaded Head – In addition to its tank, the Hayward CSPAXI11 also features a 304 stainless steel heating element and threaded head, allowing it to perform at its best for years and get every ounce of heat possible.

Safety Sensor Heating Element – Although it features a simple time-tested design, its stainless steel heating element is equipped with a safety sensor to minimize the risk of fire and provide years of hassle-free use.

Heater on Indicator Light – It may not have a fancy LED control panel like many of today’s larger and more expensive swimming pool heaters, but the Hayward CSPAXI11 does have a handy “Heater On” indicator light that tells you when its working its magic and warming your pool or spa.

Eco-Friendly Design – While it runs on electricity and isn’t as “green” as a solar-powered unit, it doesn’t emit dangerous gases like propane or natural gas pool heaters, making it an eco-friendly pool heating solution.

What We Like

As one of the best-selling spa heaters on the market today, it provides all of the capabilities and many of the sophisticated features found on larger, much more expensive units. It may not be a gas powered induced draft system capable of cranking out 400,000 BTUs and heating any pool, but this compact and highly efficient electric resistance spa heater packs a powerful punch and is an excellent heating option for any spa or small above ground pool.

In addition to being highly efficient, it is super compact and easy to install. Unlike large natural gas or propane swimming pool heaters, there are no gas connections or gas lines to worry about and the electric unit barely takes up any room at all. Combined with its quiet operation, you’ll barely even notice it, whether it’s running or not.

Best of all, the Hayward CSPAXI11 11-Kilowatt Electric Spa Heater is much less expensive than traditional natural gas and propane pool heaters. When you consider its incredible efficiency as well, this pool heater is remarkably affordable to own and operate. With so much to offer at such an affordable price, the Hayward CSPAXI11 is tough to beat and arguably the best spa and small pool heater around.

The Limitations

While inexpensive to own and operate, it only produces 37,000 BTUs, which means it’s limited in its abilities. As its name suggests, this heater is a wonderful spa heater, and although it works great for small above ground pools as well, it definitely won’t turn a frigid 20,000-gallon pool into a warm tropical paradise overnight.