Rheem 18kW 240V Tankless Electric Water Heater, Gray

We have been please with this water heater. The size is exactly what we needed. It works well to heat the water in our 3 br/2.5 ba house. It is energy efficient.

a 10+ year old rheem tank needed to be replaced. it wasn't broken but end of service life. and so much so if you drain it. after a lot of research I decided to go with tankless. fearful at first because hey is this truly better? the idea of having on demand seemed appealing. cost savings, of course. but then what type to get?!In the end I settled for a 18k rheem. ecosmart is also well reviewed, but supposedly this is just a rebranded rheem? (like dewalt and black/decker).It is super easy to install. it is small, frees up space, another bonus. costing half of a tank heater.if you can do it yourself... the installation cost is high, as you will have to run new electric and change some plumbing, but that is no biggy. you'll spend about $60 for a valve kit, $50 sharkbites and pex and some for the 8 gauge wire (that can add up if it is a long run btw). for this model you need 2x40amp breakersthe water is instantly hot, it easily serves 2 showers, one shower+dishwasher and laundry (tested!) I am very very impressed.also it feels cleaner as there is no water sitting in the tank (you should have seen the drain I had to do from the old tank to get it out of the way).highly recommend a tankless heater and this model works for our household.note: read about technical issues, so far all good, but will update if experienced.installation cost will add up if you can't do it yourself and requires logistics (between plumber and electrician).another installation note: when you get a valve kit with pressure relief (required by most code), it is effectively a gender changer. so when you get flexible hose (female), you need a M/M nipple to attach it to the valve kit... (that is another $20 for 2 nipples to take into consideration). That nipple needs to be taped on the valve attach side, the flex hose side has a o-ring and doesnt need tape (and don't add it either as it will leak)

Great electric water heater with user friendly install. Make sure to read the manual. I purchased the 18kw system. Depending on the state you live in, depends on if it will run up to two showers at the same time. We're only able to run one, as our outlet temperature is too cold and I have to run an on-line flow regulator at 2.0 gallons per minute. Not an issue for the most part, it'll end up saving on water I'm the end.Things to note:The temperature and pressure of your cold water (inlet) determines how it works out of the box. Read the manual because you will likely need an inlet flow regulator. This will fix the issue if the heater displays and "E5" error code. The error code means the water is leaving the heater too fast for it to heat, leaving you with like warm water.Because it's electric, you may notice light fixtures blinking when running hot water. This is due in part because of the power draw of the heater, but also because the fixtures or outdated/old. I have led recessed lighting and led light bulbs in some rooms. They have no issues, but my other light fixtures that are not led, will blink when running hot water. A system like this will "expose" older hardware.Make sure you have the water shut off valve before the water filter. The water filter helps delay the build up of water deposits in the water heater, which extends the life and make maintenance of the heater easy.

New Review:Ok, this lasted 26 months before I finally ripped it off the wall and replaced it. It had failed three times in that 26 months, and this was the last straw for me.After almost exactly one year, one of the heating elements fell apart. It was literally in pieces. I replaced the bad element with a third-party element, and almost exactly one year later, the second factory heating element fell apart, too. My water has very low mineral content, but after the first one failed, I cleaned the elements every six months along with flushing the whole system. That still didn’t keep the factory elements from failing. The third-party elements looked fine. I bought some spares just in case.Finally, last weekend I started noticing that the water coming out of the tap was CRAZY hot. When I started looking for the problem, I found that one of the heating elements was stuck on all of the time. The water would just keep heating up inside until the thermal protection circuit turned it off. Something in the electronics had failed.There was another issue with the water heater unrelated to these failures, too. I have solar panels on my roof, and I found that whenever someone would turn on the hot water, the solar inverter would turn off. The water heater was injecting too much electrical noise onto my power lines, which the inverter didn’t like. There is absolutely zero electrical noise filtering on the water heater, so I added my own. This fixed the solar problem, but the filter that I added consumed some power all of the time, so it wasn’t saving me energy like I’d wanted.I replaced it earlier this week with a 24kW model from a different manufacturer thar I found locally. The new one, even though it has a higher power rating, uses nearly half of the energy required by the Rheem to take a shower, 7kW vs 12kW. Since it has a higher power rating, it’s easier to use hot water at multiple points simultaneously. It also has a dynamically adjusting flow meter, compared to the Rheem where I needed to add an external flow restrictor.Don’t buy this heater. Spend a few dollars more and get something that is built better, doesn’t constantly break down, and doesn’t cost as much to operate. Get a Stiebel Eltron Tempra 24 Plus, which costs a bit more up front, but works much, much better.Original Review:A week shy of one year ago, I purchased this to replace the old water heater in my home that had quit working. The installation was easy, it only took me an hour or so to swap out, and it worked great. For a year.My warranty will expire in three days, and the water heater stopped working a few days ago. It wasn’t completely dead, and it would heat the water to around 85 degrees, but that still makes a miserable shower.I called the warranty department, and they sent me a troubleshooting guide. Using this guide, I determined that one of the heating elements was open. Honestly, I didn’t feel like it was worth the effort of trying to get this fixed under warranty, so I ordered a replacement (two, so I could replace them both) 9kW heating element here on Amazon and they were delivered the next day.The maintenance instructions say that you should pull the elements out every 6-12 months and soak them in vinegar to remove any scale, but admittedly, I hadn’t done that. My water is very soft with a low mineral count, so I tend to neglect things like this.When I removed the bad element, there were no mineral or calcium deposits on it, but the element was in horrible shape. It was all burned up, with gaping holes, twisted metal, and exposed, broken metal coils. The other element looked perfect. The bad one looked like it had been in a furnace.I replaced the elements with new ones, and it’s operational again.I’m happy with this heater while it is working, but I don’t know if I’m crazy about possibly needing to replace the elements once a year. Hopefully, I just had bad luck with the one element.