Electric Spa Heaters
Review, Buying Tips, and Best Models

What is better than to arrive from hard work and get into a hot tub or spa to relax and rejuvenate sore muscles and joints?

Surely it will make you feel amazing and shortly stress-free. This works only if the spa/tub operates with hot water.

Ecosmart pool and spa heater

This is why you should buy one of the quality electric spa heaters. Electric-powered spa heaters are designed to provide reliable, high-performing, and efficient operations for a long time, no matter the climate. Here we will tell you why electric spa heaters are so useful and why you need one!

Electric spa heaters are very similar to the heaters you use for heating pools. They have the same pumping feature, come in similar cabinets, and sometimes even work for both spas and pools without problems. However, not all of them will offer the same effect you are looking for.

This makes it not only harder to choose but somehow confusing, so we’ve decided to give you a better idea of what to go for and how to pick the right one. Keep reading and find out!

Electric spa heaters: Benefits and differences

We all know that when it comes to effectiveness, gas heaters may win the whole battle. However, the gas is often affecting the environment, costs a lot, and makes devices prone to break faster due to constant fire and gas combustion exposure.

Then you have heat pumps, which are superbly efficient but don’t offer as much performance – they heat water much slower than other types. They cost more at first, and installation costs may also go up exponentially. They offer little to no damage to the environment.

On the other hand, electric spa heaters are more efficient, provide superior heating, don’t damage the environment as much, and can still be as effective as a gas heater or even more efficient. Sometimes, electric heaters are even cheaper than gas heaters, so you have outstanding results just there.

Here are a few other advantages you get with electric spa heaters:

  • Perfect for moderate climates: work better in warmer areas, but mildly cold places are also fitting.
  • Efficiency is over 90%, which is better than in gas heaters, and the energy consumption is lowered exponentially.
  • Electric spa heaters can be installed practically anywhere: they are small, don’t weigh as much, and provide convenient designs.
  • Operating an electric heater is simple.
  • Much quieter and stress-free: they work seamlessly without problems causing little to no noise, even at high-performance levels.
  • Cleaner water and environment.

NoteProfessional installation and repair are recommended. Find local plumbers and get FREE Quotes!

How to buy electric spa heaters: What to look for!

Capacity / BTU / kW

The electric heaters come with a power measurement in BTU or kW. This tells you how powerful and how much heating capacity a device can provide. Typically, spa heaters have between 40,000 and 150,000 BTUs. This is more than enough for small, medium, and large-sized spas. However, you may find some that have even more BTU and provide superior performance, faster heating capacity, and eventually fit larger spas or pools.

Another way to know the capacity of a heater is by looking into its wattage. Generally, spa heaters come in power ranging from 1.5 kW models to 11 kW models, even up to 15 kW for the larger spas. Of course, the less kW available, the less power a device has.


Now that you know about BTU or spa capacity, it is time to learn what size you need to look for. It is important to know all the measurements of your hot tub or spa as well as the amount of water (in gallons) it usually works with (or volume). This way you will be able to make a better decision on what heater to buy.

We recommend using the old and effective measurement of 700 BTU for each gallon of water. This means that for every 70,000 BTU, you will be able to heat a 100-gallon spa in less than one hour.

For kW measured heaters, you should know that 1 kW of power heats a gallon of water in seven minutes. Alternatively, by using the 5.5 kW heater, you can heat 100 gallons of water in 80 minutes.

However, it all depends on the efficiency of the heater you choose and the desired temperature. Higher temperatures will take more time to achieve than you may think.

Desired temperature range for any spa is between 101 and 103 F (should not exceed 104 F). Since the spas are thermostatically controlled, the danger of exposing yourself to high temperatures is significantly reduced.

Note: Heat-up time, as the time required to heat the water to the desired temperature, is an important detail to use when sizing the heater.

You might also want to take into consideration the wind speed, and altitude as those can increase the surface heat loss. Or, the shade, because it might be the reason why you need to upsize the heater.

Top selling electric spa heaters review 2018!

Hayward electric spa heater - C-SPA series

Advanced and highly reliable, the Hayward C-SPA series can deliver outstanding performance without problems, and at the comfort you would expect. It will heat your 200-gallon spa in just 80 minutes and may provide superior performance to keep emissions low and get the best out of every kW of power.

Overall, you could say it offers around 40,000 BTU in its largest model. With high power, reliable stainless steel construction, and an excellent user-friendly interface, the heater may be a magnificent choice for any homeowner.

Benefits of using the electric C-SPA series heater:

  • Reliable construction may offer up to 15 years of worry-free use
  • Excellent tank build provides better resistance to weather and impacts
  • Exceptional efficiency & performance
  • Really small & reliable design for durability and convenience

Raypak Spa-Pak ELS

Efficiency at its maximum, Raypak Spa-Pak is a spa heater for all users who want a reliable yet incredibly performance-oriented device. Coming with the resistant cabinet and superior 100% copper tubes, you won’t have any problem with this device at all.

Both the 5.5 kW and the 11 kW models are effective for heating and will last up to 15 years without problems. Having a Raypak heater is having the quality that lasts and delivers.

Benefits of using the Raypak Spa-Pak ELS:

  • Excellent construction makes the device more resistant and reliable
  • Outstanding brass header build will keep corrosion away from water
  • The robust heating element keeps performance on peak
  • Works with any 240v connection without problems
  • Offers amazing efficiency only Raypak provides

Ecosmart Smart Spa

Operating with the latest technology and providing a better pressure switch, Ecosmart Smart Spa is one of the most reliable models in the market. This Smart SPA will help you get your spa warm faster than many others, delivering at the same time one of the smallest and most convenient designs.

At 11 kW and a digital thermostat and control display, this device is very easy to use, reliable, and effective. You won’t have any problem with the Ecosmart Smart SPA 11 – and it will help you heat your spa for years.

Benefits of using the Ecosmart Smart SPA 11:

  • One of the most reliable constructions out there
  • Offers on-demand heating for more continuous & long-lasting heating
  • It helps you save energy and thus monthly expenses
  • The small design saves space & is easier to install
  • Easy to use digital thermostat control
  • 10 GPM activation flow saves water and keeps performance at peak


As you can see, choosing electric spa heaters can be very easy as long as you know what you’re going for. With the three options we have here from Hayward, Raypak, and Ecosmart, you won’t have any problem finding a high-quality device for your spa.

So, what are you waiting for? We are here to help you out in your search, so choose one of these or let us know how we can help you. The right electric spa heater is waiting for you!