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Thermoflow Electric Mini Tank Water Heater, 4.0 Gallon 120V Corded Under Sink Small Hot Water Heater for Point of Use Instant Hot Water

  • Based on 755 reviews
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Returnable until Jan 31, 2026

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Style: 4.0 Gallons


Features

  • Instant Sink Hot Water - 4 gallons capacity, point-of-use mini tank water heater fits under your sink to provide immediate hot water right where you need it. Eliminate time for hot water. Dimensions: 18H x 12.2W x 11D inches, 2.6ft cord Plugin to use.
  • Long life Service - This compact mini tank water heater use stainless steel tank to reduce corrosion and maintenance.
  • Save Energy - Fast recovery and thermal efficiency up to 98% using stainless steel heating element, 3-layer EPS foaming insulation reducing heat lost, provide you more hot water with less power power consumption.
  • Safe & Reliable - Over-heat protection, auto cut-off electricity if not hot water come out, IPX24 water proof, 2.6ft plug in cord, suit for kitchen, bathroom, bar, school, hospital, office and RV.
  • NOTES - Please verify that this model is the right size for your hot water needs and electrical requirements before purchase & installation. Dimensions: 18H x 12.2W x 11D inches; Weight: 14 lbs; Water connections: 1/2 inch NPT, Electrical requirements: 1.5 kW, 120 Volts. Max pressure: 150PSI. Nominal current: 13A.

Brand: thermoflow


Product Dimensions: 12.2"W x 18"H


Special Feature: Quickly Hot Water Supply, Compact Size Saves Space,Two Modes Optional, suitable for any season.


Color: White


Wattage: 1500 watts


Brand: ‎thermoflow


Product Dimensions: ‎12.2"W x 18"H


Special Feature: ‎Quickly Hot Water Supply, Compact Size Saves Space,Two Modes Optional, suitable for any season.


Color: ‎White


Wattage: ‎1500 watts


Voltage: ‎120 Volts


Maximum Temperature: ‎167 Degrees Fahrenheit


Heat Output: ‎1500 Watts


Efficiency: ‎High


Maximum Operating Pressure: ‎150 Pound per Square Inch


Mounting Type: ‎floor mount or surface mount


Is Electric: ‎Yes


Manufacturer: ‎thermoflow


Item Depth: ‎11 inches


UPC: ‎630792535352


Item Weight: ‎13.16 pounds


Item model number: ‎UT15N3


Size: ‎4 Gallons


Shape: ‎Rectangular


Maximum Power: ‎1500 Watts


Installation Method: ‎Floor-Mounted


Temperature Range: ‎45-167 Degrees Fahrenheit


Special Features: ‎Quickly Hot Water Supply, Compact Size Saves Space,Two Modes Optional, suitable for any season.


Included Components: ‎1X 4 Gallons mini tank water heater, 2X 1/2 inches brass bushings, 1X instruction manual


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: March 5, 2019


Frequently asked questions

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Top Amazon Reviews


  • Use 2 of these in different ways, excellent results!
Style: 4.0 Gallons
I purchased one of these for my Florida office and it works extremely well to deliver instant hot water for hand washing, etc. I purchased another one as a pre-heater for an addition on home with long lines to the primary hot water tank. This works superbly! Instant hot water for hand washing, instant hot water for shower until the main hot water tank takes over. For the shower, the cold inlet comes from the main heater tank and the outlet feeds the shower and wash basin. Works very well, saves time and water because you needn't let the faucet run and wait for hot water to come from main tank. Love the results! Excellent product and excellent results! ... show more
Reviewed in the United States on May 6, 2024 by Charles Devers

  • A safer tank, Great size and shape, Quiet and simple to install
Style: 2.5 Gallons
After looking at a number of products that make the buyer do the protection from hot spots in the take (by adding a pressure valve that needs a drain, This product seems to take care and heat more evenly and without creating local steam from a too hot too small a heating element. Turning on for the first time I listened very close for the characteristic hiss or Pop from over aggressive heating elements - NONE Totally quiet! and the Heat time was very reasonable even quick - Temperature control very smooth with plenty of range. Size was great - having it built to SIT on the counter floor rather then requiring hang on the wall a real plus. One hit - The tank list NPT 1/2" fitting. Typical USA this is called a "compression Fit" and is NOT a FIP. And Most sinks and faucet connections are smaller, 3/8" . After a bit of fussing I found a 1/2 to 3/8 compression adapter (home depot etc) that fixed that - but I did have a challenge from the tank needing to be farther then the 30" lines available in hardware store - Found a great 4-foot with 3/8 compression on both ends from Amazon - which fit the bill perfect. only took 15-20 min to install once all the parts were found. ... show more
Reviewed in the United States on March 9, 2019 by Kindle Customer

  • Cheap fittings included in the package.
Style: 4.0 Gallons
Purchased. Had a plumber stop by to install although it appeared to be a simple installation. Plumber left and water heated up. However, after a couple of hours one of the fittings included in the package simple broke where the treads connect to the housing of the fitting. Obviously, water flooded our kitchen and my wife and I spent a couple of hours cleaning up the mess after we were able to shut off the water supply. Thankfully, we were present when it happened or there would have been major damage to our home. We have now called back the plumber and instructed him to replace not only the broken fitting, but also the other fitting as well. These are cheaply made brass-like fittings and I do not want to have to worry about them breaking again, so I'm replacing them with quality fitting. Suggest you do the same if purchasing any of these units that come with fittings. ... show more
Reviewed in the United States on December 16, 2020 by Jim N.

  • Instant hot water is great! Very easy to install.
Style: 2.5 Gallons
It works great and was very simple to hook up. I only wish it had another temperature setting. The lowest one is only like warm and the next one up is too hot for me. Some people might like it too hot to hold your hand under. I haven't tried the next higher setting. But it's great to get hot water right now and not have to waste time, electric and water waiting for it! ... show more
Reviewed in the United States on March 16, 2019 by Thomas S.

  • Thermoflow UT10 2.6 Galllon undersink water heater DOA With UPDATE
Style: 2.5 Gallons
This water heater was purchased to get us hot water "quickly" instead of a $3500 recirculating system (our plumber quoted us). It arrived DOA (Dead On Arrival). I did not learn it was DOA until the very end of the install (the directions are specific, don't apply electricity to the heating element until you have filled the tank with water). Hooking it up was a bit problematic. I had to purchase about $55 worth of hoses, tees, nipples, etc. to hook it up. Of course, you are laying on your back under the sink and disposal cabinet the entire time. When finally plumbed, I turned on the water, the tank filled and I put the dial on ECO mode (supposedly about 131 degrees which is plenty hot for mixing with cold water to do dishes). No light comes on, no water heats, nothing. I tried Thermoflow's suggested diagnosis. It said to push the reset button on the back of the unit. There was a sticker that read RESET but there was nothing near where it was located. So, I go on their website and go to support. It's an empty page (GRRRR). So, I call their support line (open 8-5 Colorado time). The first young man I talked to told me to pull the RESET sticker off to see if the reset button was under it. No joy, it wasn't there. Please take a picture of the back of the unit and send it to us; we'll send it to engineering and get you an answer in another 24 hours. I lost my temper, hung up and cooled down. I was so angry this young support person did not know where the reset button was. I called support back, got someone else on the line and we figured out where the button was (on the back but you need a ballpoint pen point to push it in. Because it was plumbed in, it was difficult to get to but manageable. Still no light or hot water. Back into the box and returned it to Amazon. This is a 1 star review because it was DOA and support initially was terrible. I packed it back up and am awaiting UPS pickup. I did however order another one (same unit). I will update this review if that one works as planned. If it doesn't, No update will occur. I don't like to flame a manufacturer but their website was only about selling water heaters and nothing about product support. FUBAR! UPDATE October 1, 2019: I've raised my original 1 star review to 4 stars. I ordered a replacement and it arrived within the promised 2 days. The refund for the original was received within 1 day of pickup by UPS. Amazon is amazingly efficient AND effective. The new install went quickly and I learned that the unit has a voltage protection feature built in. If more than one appliance is plugged into the same receptacle, the unit senses it and will not power on. Easy to correct that problem. Water was scalding hot within 20 minutes. The "instant hot water" is now available. ... show more
Reviewed in the United States on September 28, 2019 by Skip. Johnson

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