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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 1,009 reviews
Condition: New
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Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon

Arrives Saturday, May 31
Order within 18 hours and 15 minutes
Available payment plans shown during checkout

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


Efficiency: ‎High


Maximum Pressure: ‎150 Pound per Square Inch


Mounting Type: ‎floor mount or surface mount


Is Electric: ‎Yes


Style: ‎4.0 Gallons


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

If you place your order now, the estimated arrival date for this product is: Saturday, May 31

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Finally, Warm faucet water in winter!
Style: 2.5 Gallons
After suffering through winter after winter of cold faucet water in our patient bathroom, and after plumber after plumber said there was nothing which could be done other than wrapping pipes with plug-in pipe warmers (which did not work), I conducted my own research and came across stand alone water heaters. I read through reviews of many such products and saw complaints about rusting and product failure. I kept researching until I came across this product and felt confident in purchasing it. My contractor installed it after needing to install a water-resistant outlet in the bathroom and after drilling into the drain pipe and connecting the hoses. Since our patient bathroom sink has to be accessible to wheelchair patients, there is no cabinet underneath the sink. I wish this water heater tank was able to be attached to the wall but the directions say not to attach. So my contractor built a small platform for the tank to rest on so that the tank does not get contaminated when the bathroom floor is mopped. Normally by the time a person is done washing their hands, the faucet water is still ice cold. But now within a few seconds of the faucet turning on, they get warm water to wash their hands for as long as they need to wash them! I am so happy I purchased this product! ... show more
Reviewed in the United States on December 16, 2020 by big Ry

  • Not what we expected or wanted with bad design
Style: 4.0 Gallons
This is not a quality product. We ordered a new item but the box came open and was retaped. The "included" hardware was missing. We had been out of water for over a week and had to install this as no store in our immediate area (25 mi radius) sold a mini tank water heater. I'm not blaming Thermflow for the open box or missing parts. This is completely the fault of Amazon. Either they let an opened product slip by the "new" items warehouse or we were sent a pre-used product contrary to what we asked and paid for. Worst case scenario is an employee took a broken product with missing parts and replaced the new item with it. The reason is really irrelevant. The point is that we were sent a substandard item. Once my husband put the parts on and turned it on, it started leaking up top by the values. My husband, who is HVAC certified with over 20 years experience, commented that the pressure relief valve should have been installed at the factory. It also should have had its own valve and roughly placed in-between the hot & cold inputs. At the very least, it should be on the hot output to be able to relieve pressure build up. It shouldn't have been put on the cold input, where the pressure doesn't increase as rapidly. Hubby managed to stop by the leaking only to have us wake up 2 days later to find the kitchen flooded as the unit had (and still is) leaking from under the outermost white plastic cabinet. Out best guess is the Internal tank is busted. This last leak alone is enough for me to say I will never purchase a Thermflow product again. Until I can get a replacement water heater I'm forced to either live without water or have water and a kitchen that completely floods on a daily basis. ... show more
Reviewed in the United States on May 21, 2022 by DebRusty DebRusty

  • 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

  • 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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