🔥 Instant heat, zero wait—upgrade your sink game now!
The thermomate ES400B is a UL-listed, 4-gallon electric mini tank water heater delivering rapid 1440W heating power. Designed for point-of-use under-sink installation, it features a compact footprint, easy plug-in setup, and a durable gold porcelain enamel lining. With adjustable temperature control up to 140℉ and built-in pressure relief valve, it offers safe, efficient hot water on demand—perfect for kitchens, bathrooms, or as a booster to larger systems.
| Brand | thermomate |
| Product Dimensions | 4.96"W x 6.81"H |
| Special Feature | Pressure Release Valve |
| Color | White |
| Wattage | 1440 watts |
| Voltage | 120 Volts |
| Maximum Temperature | 140 Degrees Fahrenheit |
| Heat Output | 1440 Watts |
| Maximum Operating Pressure | 150 Pound per Square Inch |
| Maximum Pressure | 150 Pound per Square Inch |
| Mounting Type | Wall or Floor |
| Is Electric | Yes |
| Style | 4 Gallons |
| Manufacturer | thermomate |
| UPC | 850052972028 |
| Part Number | ES400B |
| Item Weight | 20 pounds |
| Item model number | ES400B |
| Special Features | Pressure Release Valve |
| Included Components | T&P Valve |
| Batteries Required? | No |
T**.
Works great
Works great in my RV, plenty of hot water.
K**R
Great product
Simple to install. Well made. Solved my problem of having to wait long periods of time for water to get hot because my regular water heater is so far from the kitchen.
T**E
A POS heater that's not a POS!
It was very easy to install. I didn't have room in the sink cabinet so I installed it directly below in the basement. It provides hot water instantly, which is awesome. Only complaint is that the power cable is not very long. I had to mount it about a foot from the wall receptacle which wasn't where I wanted it to be.
K**P
Finally…instant hot water!
Working great and easy install
K**O
Ease of installation
In my remodeling business I often look for easy to install, practical items when I do kitchen and bathroom remodels. I highly recommend this water heater...it is lightweight, easy to use runs off of a traditional 15 amp circuit and hooks up in virtually minutes if you have the plumbing right there. I found it very practical for the kitchen I was remodeling and found it to be very economical! The delivery was fast! ( thank you Amazon hehe) and I got the customers up and running in just one day! The installation instructions for very thorough and easy to follow for even a DIY-er! I highly recommend this product👍🏽
M**N
Inexpensive and reliable
Is the first time having a tankless water heater.I do appreciate that as soon I use it to shower ,hot water came out. It is perfect for 2 people.I just love my water heater, it holds the hot water for at least 15 to 20 minute. Enough time for a shower.
G**O
Product received broken.
wasted time....and time is money.
C**E
Quick way to get hot water now if faucet is a mile from the water heater!
Purchased because it took forever to get hot water from the heater to the kitchen sink. Had to run nearly a gallon of water before it got warm. So, I hung this puppy under the sink, plugged it into a private outlet. Problem solved! By the time this unit runs out of hot water, warm water is entering from the main water heater plumbing. The ONLY issue is that the thermostat is very "loose". Meaning the delta-T (temperature swing) is a bit excessive. I set it for about 120ºF but the actual water temperature can vary from 98 to about 125. Funny thing is that if it sits for many hours, then draw water, the water is just luke warm, like shower temperature. Run a quart or more, shut water off, come back in 10 minuets and find the water hot and nearly steaming. Maybe it's blessing in disguise, meaning it relaxes when not being used to save energy, then when it sees use, kicks in to heat it up? Really takes only like 5 min to get decently hot if you don't crank on the water flow. But, ya, worth it anyway to have nearly instant almost hot water!
Trustpilot
1 month ago
1 week ago
