Atmor AT 900 03 Review


Atmor AT-900-03 is an extremely efficient and energy saving water heater. You can easily get your regular electricity bill lowered to up to 30% through this unit. It provides an all-round solution for residents of cold regions because usually water heating is the second biggest energy expense for those households. This is a time-saving, energy-conserving and eco-friendly option. You can receive endless supply of hot water without wasting any time in waiting for water to heat-up. This unit is perfect for both residential and commercial usage. It has been elegantly designed so would look amazing wherever you install it in your home or office. Dimension wide the unit is 7.29x11.82x3.55” wide and weighs just over 3.4lbs. Atomr AT-900-03 has over-heat protection enabled and the unit can be easily mounted on the wall.

The Pros & Cons of the Atmor AT 900


  • Supplies hot water instantly when required
  • Doesn’t waste water at all because its heating mechanism don’t involve storing water
  • It is a compact and light-weight device so you can easily mount it at any nook or corner to keep it out of kids’ reach


  • This is not a plug-in tankless heater and therefore, needs to be installed
  • Installation can be tricky for those not familiar with electrical equipment and this means you may need help and assistance of experts to install it

Installation and Specifications

This heater needs to be mounted against the wall and most appropriate would be to install it somewhere out of sight and near the point of use such as under the sink. Installation wise, this unit is very user-friendly. Just got for 110v installation for which you will need a 30amp circuit breaker and 10AWG wiring.


Assembled Depth7.29"
Assembled Height3.55"
Assembled Width11.82"
Product Depth3.55"
Product Height7.29
Product Width11.82
Water Connection Size0.5
Amperage (amps)27
Electric Product TypePoint of Use
Finish FamilyWhite
Flow Rate @ 35 F Rise (gallons/min)0.6 gal (US)/min
Flow Rate @ 45 F Rise (gallons/min)0.5 gal
Fuel TypeElectric
Maximum Temperature (F)130
Minimum Activation Rate (gpm)0.5
Minimum Temperature (F)65
Product Weight (lb.)3.4 lb
Residential/Commercial/industrial UseResidential or commercial
Voltage (volts)110
Water Connection LocationBottom
Water Heater FeaturesOverheat Protection,Wall Mountable
Wattage (watts)3000

Common Problems

A common issue that users of this unit face is related to the manufacturing of the housing because the wires can be connected only from the back and not from the sides or bottom. Even while installing through the back opening, the clearance is not enough and wires are required to be clamped in the opening instead of being run through it. However, on the positive side, this unit is a multi-purpose option for indoor usage. It is a durable product that ensures long lifespan and since it has been made from recycled material therefore, it is eco-friendly as well. You can save a lot of your money because it just heats water when you demand it.


This is definitely a good buy for the environmentally conscious as this is a model that doesn’t waste water and energy. It is also very practical as you can get an endless supply of hot water and only when you need it. It has a particularly long life span as it also does not allow for scale or mineral build up since the water it supplies reaches very high hot temperatures.

You can buy the Atmor AT 900 on Amazon.

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