EcoSmartSMART POOL 18 Electric Tankless Pool Heater, 18kW, 240 Volt, 75 Amps with Self Modulating Technology

I installed this heater for my 13k inground pool with electrical service approx 120ft away using #6 wire. As long as you understand how to design the electrical to support this huge power draw and understand the tradeoffs, it works great. Be sure you calculate the voltage drop at the end of your wiring run as that will affect the heater performance. Be sure your breakers are rated for the correct ambient and termination temps because the breakers can get really hot especially if you're heating your pool 24/7 for several days and your service panel is in direct sun. Ensure your electrician understands this.I wanted a heater where I could raise the pool temp to 85F with two days notice anytime during pool season, and this does that. In socal in the winter I can heat my pool from 55F to 85F in approx 4-5 days (but you pay a ton of money in electricity to do so). During spring/summer I can easily raise the temp at least 10-15 degrees per day of use.Watch out for the pool chemistry which directly impacts longevity of the heating elements. Follow the manual instructions and you'll be good. I also drain mine when not in use to further extend longevity.The way this heater works is that is has 3 9kw heating elements and draws the full 27k (9kw x 3) when heating up to the set temp. Once at the set temp, it holds the water temp by cycling the three 9kw heating elements on and off. When the water temp stabilizes it then cycles one 9kw heating element on and off to maintain the water temp.The on-off cycling, especially at 27kw, can have the unintended effect of lights flickering in the house (especially LED lights) due to the momentary voltage drop across the entire house. Depending on your electrical service and neighborhood that voltage drop could result in momentary voltages as low as 80V that I've seen.For a future version I would recommend improving the on-off cycling (when maintaining a set temperature). If there's a way to ramp power draw from zero to 9kw/27kw that would help with voltage drops and lights flickering.

First off I have never taken the time to write a review before.May of 2013 we purchased the ecosmart pool 27kw for our 15,000 gallon pool, we loved the idea that it was small and silent.I gave it one star not because it didn't heat the pool, which it did and did very well, but because we could never figure out why it kept turing on and off. The unit is suppose to heat the pool turn off, drop 5 degrees and then turn back on. If this would have been the case I would not be writing this review. Instead it kept is a constant 90 degrees which is where we set the temperature on the unit.However what I noticed was when it hit the temperature that we set to 90 degrees, the house lights would start dimming and I would go out to the unit and the temperature reading would start fluctuating from 90 degrees to 89 degrees making the unit come on and off. I also hook up my amp reader to make absolutely sure and indeed this was the case. As many people may or may not know it takes a lot of electricity to turn on a 27kw unit and when it's turning on and off that is a tremendous amount of wasted energy and from that it tripled our electric bill.I called customer service which was great and they sent me a new mother board and two new thermostats, replaced the mother board and thermostats with the new ones and the same thing happened.At this point I called an electrician and tried to trouble shoot the problem over the phone which we never came up with anything.The unit was completely hooked up by a licensed electrician with number 8 copper wire on 3 separate 50amp breakers, one for each heating element on a 200amp supply which is plenty of power to run the unit.This continued for awhile with many calls to ecosmart customer service, nothing changed but they sent me more parts and eventually a second unit. The second unit did the same thing.After that I called a licensed electrician and had them come out and look at the unit to see if there is anything that would interfere with the heater that would make it bounce back of forth causing the unit to go off and on. There was nothing and he said everything was perfect as far as it being hooked up correctly and this was by a different licensed electrician than the one who originally set it up.I took it a step further and went to my local pool and spa place where I sat down with a technician and showed him all the videos that I had taken of the unit and how everything was set up. He was is dismay, he said that most likely no one would notice the unit shutting off and on like that or that no one has complained because the company is relatively new, and he could not see any reason why the unit would turn off and on like that. We spoke for about an hour going over everything that could be possible and he said I should return the unit.I called the company and tried to return the unit and I was told that they do not do returns, I bought this on amazon and of course it's been to long for me to return it.Ecosmart knows how many times i've called and tried to get this unit to work correctly and have tried everything I could think of.If you looking at this unit and think you might save money, you won't, you'll end up spending way more money on your electric bill than it's worth.I have since then bought a heat pump and it works perfect, not shutting on and off and its right next to where the ecosmart pool 27 was using the same wiring that we used for the ecosmart pool 27, except the electrician had to install a 50amp gfi breaker for the heat pump. With all that being said I know our electric bill is going to drop significantly paying for the heat pump in one year compared to the cost of running the ecosmart pool 27kw heater...I'm not telling you to not buy it, but if you spend a little more upfront you can buy a way more energy efficient pool heater. We only use our pool in the late spring through sumer and end in the early fall so the heat pump works great for that. If you want a pool heater year round then you might have to look at other alternatives.Good luck on your pool heater search.