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Performance 18 kW Self-Modulating 3.51 GPM Tankless Electric Water Heater

$449.00
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  • Provides continuous on-demand hot water
  • Energy and cost savings of up to 34% in whole-home installations
  • Water heater requires 2 x 40 AMP double pole breakers
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Price:
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Product Overview

Get hot water for your space with this Performance Self-Modulating Tankless Electric Water Heater. This energy-efficient water heater delivers an endless hot water supply and consistent temperature with a self-modulating technology that adjusts energy based on your hot water needs. With the electronic thermostatic temperature, you can easily read the incoming water temperature and control it in one-degree increments. Point-of-use installation and compact size makes this Performance water heater a convenient choice.
  • Energy and cost savings: heats water only when it is needed for savings of up to 50% on water heating costs when used in a point-of-use application or 34% when used as a whole-home solution
  • Instant, continuous hot water: instantly provides ample hot water for up to 2 showers and 2 faucets (review selection guide below to confirm this water heater will provide the hot water needed based on your geographic location)
  • Space savings: small, compact design fits perfectly in tight places like under cabinets and sinks
  • Great investment and value: energy cost savings and a 5-year heat exchanger and 1-year parts limited warranty
  • Easy to adjust: electronic temperature control adjustable in 1-degree increments from 80-140 degrees F with easy-to-read display (Celsius and Fahrenheit compatible)
  • Easy installation: compatible with 3/4 in. water connectors for flex hose installation and no venting or T and P valve required for Easy installation (professional installation recommended)
  • Easy to maintain: durable, easy-to-replace heating elements
  • A reliable hot water solution from Rheem, the global leader in water heating
  • Before purchase and installation, please verify that you have the proper electrical requirements for your chosen heater
  • ETL Listed to UL-499 and CAN/CSA-C22.2 No. 64



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Performance 18 kW Self-Modulating 3.51 GPM Tankless Electric Water Heater
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BrandRheemStiebel EltronStiebel EltronStiebel Eltron
NamePerformance 18 kW Self-Modulating 3.51 GPM Tankless Electric Water HeaterTempra 15 Plus Adv Flow Control & Self-Modulating 14.4 kW 2.93 GPM Compact Residential Electric Tankless Water HeaterTempra 20 Plus Advanced Flow Control & Self-Modulating 20 kW 3.90 GPM Compact Residential Electric Tankless Water HeaterTempra 36 Plus Advanced Flow Control & Self-Modulating 36 kW 7.03 GPM Compact Residential Electric Tankless Water Heater
Price
$45900
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$84900
Ratings
(1786)
(9)
(122)
(17)
Required Volt Connection240 volt240 volt240 volt240 volt
Wattage (watts)18000 W14400 W19200 W36000 W
Application TypeResidentialResidentialResidentialResidential
Indoor/OutdoorIndoorIndoorIndoorIndoor
Water Heater FeaturesWall MountedOverheat Protection,Wall MountedOverheat Protection,Wall MountedOverheat Protection,Wall Mounted
Fuel TypeElectricElectricElectricElectric
Number of Showers1-21-21-21-3
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Customer Reviews

  • 4.1
    out of 1,795 reviews
  • 71%recommend this product
Filter by:
Showing 1-10 of 1,795 reviews
Read up before you buy
Understand flow rate, temp rise before you buy. If you live where water is 65 you may be satisfied with the output of this unit but depends how many faucets are opened at the same time. Understand brkr requirements. House needs 200 amp svc. Unit needs 112 amps at 220v. If you don't have space for 4-40amp 220 brkrs you will need a subpanel. Do some calcs-are you planning to run an electric stove or dryer, hvac, and showers at the same time, won't work.
by
    • Recommended
    4 found this review helpful
    lasts about a year
    we are very space conscious so bought a 13 Kw rheem tankless. we only get about a year out of the first one before it's overheating and fails. buy another one which manages to get to a year and a half before popping the circuit breaker. Turns out the copper lined heating element inside is corroding and bursting. not recommended if you have hard water I suppose.
    by
      2 found this review helpful
      Very Happy
      I bought this unit because are hot water tank was over 50 feet from the kitchen and one of our bath rooms and it took for ever to get hot water to that end of the house. I did the installation my self. The water hook ups were easy. I used Pex flush valves that I got at Home Depot and had no problems. The thermostat on the unit goes to 140 degrees but I have it set at 125 and that is hot enough for us. I am very happy with this unit. We have plenty of hot water for the kitchen and bath room and we don't have to wait for ever like we use to.
      by
      • Verified Purchase
      • Recommended
      3 found this review helpful
      Great value for your money.
      Works as advertised.
      by
      • Verified Purchase
      • Recommended
      1 found this review helpful
      East to install/works perfect makes wife happy
      18kw I live in Orlando Fl - two bath house family of 5. Kids 12-6-1 we can all take a bath and or shower in the evening without having to wait for the water heater to hear back up. My 12 year old likes to take hr long showers - I just go turn the temp down and or turn off the water if she won't get out. It's become a game of sort East install-I did it myself including new wire to sub panel. Saves space and works! Get one you won't regret it. Added a utility sink where the old tank was
      by
        • Recommended
        1 found this review helpful
        Install is Difficult
        Happy with the cost, same as a conventional. Wish the unit came with other parts like an insulated bushing assembly for the 3 heavy duty wires that go INTO the water heater for its power installation. Bad mojo to leave the wires up against the edges of the metal like that. The reason why I give 3 stars is because of that, because I had to make a couple trips back and forth to retrieve THOSE items.
        by
          • Recommended
          2 found this review helpful
          Performance 24 kw Self-Modulating 4.68 GPM
          Ran electric, 3 40-amp bi-pole breakers, 3pair 8awg and 1 8awg ground. Line drops to 1/2" copper 12' in home, went to 3/4" 10' before tankless and drop back to 1/2" 10' after. I have had no issue with brass fitting and pex push-in. There is slightly longer lag time than from previous gas tank but it's seconds and nothing that concerns me. I will be adding an 8kw Rheem point of use, when I upgrade my 1/2 bath to full bath after saving space from water heater :)
          by
            • Recommended
            4 found this review helpful
            Among the best!
            While I’ve had two other on demand hot water heaters in the last 30 years this is my first Rheem. It’s by far the easiest to install and adjust.
            by
            • Verified Purchase
            • Recommended
            2 found this review helpful
            Painless to Install, Works Great!
            I had read a number of reviews where there was an issue with leaking connections. This came with two options, compression fitting or threaded. I opted for threaded as I needed to adapt to 1/2" PEX. The set of fittings each had a chamfer to accept the compression ring (aka "olive"). So I cut about an inch of copper tubing for the olive to remain in perfect position once assembled. Coated it with sealing paste lightly. And for the threads I used thread past along with Teflon tape. (Yes, overkill. But there were a lot of complaints so I did the belts and suspenders approach.) And that was four months ago and the unit is performing flawlessly! Zero leaks.
            by
              • Recommended
              2 found this review helpful
              It doesn’t work!!!!!
              It does not heat the water. Will not stay hot. Goes cold when showering.Blew cable off twice sending water all over the house!!!!!?I have had for two years and has not worked properly from beginning. Do not waste you time and money on this piece of crap!!!!!!!
              by
                22 found this review helpful
                Showing 1-10 of 1,795 reviews