EcoSmart Water Heater Problems [7 Easy Solutions]

The most common EcoSmart water heater problems are:

  • Heater not turning on or heating
  • Heater tripping the breaker
  • Problem with flow meter & thermistor
  • Heater leaking 
  • And error codes indicating specific issues.
ecosmart water heater problems

Whatever the problems, we will explore them with simple solutions in our today’s EcoSmart tankless water heater troubleshooting guide. 

EcoSmart Water Heater Problems [7 Easy Solutions]

While using an Ecosmart water heater, you may encounter a couple of problems. Below are some of the common problems with this water heater and their remedies. Let’s start with the number one problem of Ecosmart water heaters…

01. EcoSmart Water Heater Won’t Turn On

Remember, a typical water heater needs at least 240 volts to work properly. In the event that the power is less than this, the unit will not start. It is actually an error code (S103), which refers to this issue. If the EcoSmart water heater won’t turn on, then there can be several reasons, such as:

  • Problems with the electrical connection causing the unit to not get enough power
  • The flowmeter is unable to turn the heater on
  • If the inline fuse blew out 

How To Fix:

When the EcoSmart water heater won’t turn on, then the display won’t appear either. Luckily, this issue can be solved by taking some careful measures. Perhaps, you can follow these measures:

  • Inspect the electrical wires to check if there is any problem. Additionally, use a voltmeter to check the voltage
  • Verify that there are no debris or sediments blocking the flowmeter
  • Get experts to repair the blown-out fuses

02. Problem With The Flow Meter

The flow meter on the intake side of the Ecosmart water heater is crucial since it turns the heater on. Yet, there are a few reasons why the Ecosmart flow meter can be giving you some trouble, such as:

  • Obstruction or blockage in the flow meter
  • Obstruction in the propeller
  • Interruption in free spinning
  • The LED display won’t light up

How To Fix:

If a faulty flow meter is a reason why your Ecosmart water heater is not working, then it can be fixed by following these approaches:

  • Make sure the water is flowing vigorously to match the water display’s flow
  • Flash the particles that are blocking the propeller
  • Clear the flow meter with high water pressure
  • Contact a professional to confirm whether or not the meter is indeed detecting water flow. 

03. Problem With The Thermistor

The Ecosmart water heater has 2 thermistors. The red wire is for the thermistor on the outside, whereas the yellow wire is for the inlet side thermistor. The heater won’t be able to generate hot water if there is a problem with any of these thermistors.   

These thermistors may go bad for the following reasons,

  • If the water heater’s elements are not receiving electricity from the thermistors control board
  • In the event that the LED display is inactive or shows a specific temperature
  • If the thermistors are disconnected

How To Fix:

The Ecosmart water heater can still operate when there are minor problems with any of the thermistors. Follow these steps to fix the thermistors issue:

  1. Make sure the position of the breaker is on the “ON” position otherwise, the thermistors won’t get power
  2. Replace the thermistors’ detached components
  3. Check whether the LED screen is showing the right temperature, not a fixed one 

04. EcoSmart Tankless Water Heater Tripping Breaker

You should inspect the water heater carefully if you notice EcoSmart tankless water heater keeps tripping the breaker. There can be many reasons for tripping breakers. Here are the mentionable ones:

  • When the thermostat malfunctions
  • When the heating elements malfunction or become faulty
  • The breaker may trip as a result of a water line leak
  • When there is a problem with the electrical connection between the main line and the water heating appliance
  • When the breaker itself wears out 

The following video may help you in order to determine the causes of tripping the breaker and how to fix it:

How To Fix:

With a few timely cautions, this issue can be solved. To prevent your EcoSmart water heater from tripping the breaker, you can follow these solutions:

  • Adjust the resistance level of the thermostat by using a multimeter. It should be 0 ohms for the (NO) thermostat and 0.5 ohms for the (NC) thermostat
  • Adjust the resistance of the heating elements according to the wattage. For instance,
    • 16 ohms for 3,500-watt elements
    • 10-11 ohms for 5,500-watt elements  
    • 12-13 ohms for 4,500-watt elements
  • Hire an electrician to inspect and fix the faulty electrical lines
  • Additionally, repair the pipes that are leaked

05. Water Heater Leaks

Of course, leaks can be a major problem for the Ecosmart water heater. There can be various reasons to cause a leak in this water heater, such as:

  • In case the plumbing connections are too tight or loose
  • When the heating elements are dirty or clogged
  • When the storage tank is corroding
  • If the cold feed condenses near the heater

How To Fix:

To prevent your Ecosmart water heater from leaking, you just need to be a little cautious and follow these approaches:

  • Identify the loose or overly tight connections and tighten them properly
  • Insulate the cold feed and make sure there is no moisture
  • Clean the heating elements every 6 months
  • To address the corrosion issue, hire an expert to check for leaks or rust in the storage tank and the water heater

06. EcoSmart Tankless Water Heater Not Heating

If the thermostat does not get the proper power, the EcoSmart water heater won’t supply hot water. However, this problem can occur due to the following reasons:

  • The thermostat becomes faulty
  • The heater is not getting enough power
  • The unit is not reaching the minimum flow rate (which should be 0.5 gallons/minute for most models)  
  • The weather is extremely cold outside

How To Fix:

When cold water comes from your Ecosmart heater, then you should not neglect this problem. Although the issue is minor, it can get serious over time. Before that, you need to solve this problem by following these actions:

  • Make sure the heater is receiving the proper amount of electricity by checking the panel
  • Ensure that the power indications on the buttons are lit
  • Remove blockages from the air intake channels and vents  
  • Reinstall and reset the circuit breaker that tripped

EcoSmart Water Heater Error Codes

You have to be aware of what the EcoSmart water heater error codes signify. The diagnostic process will be simplified as a result. Eventually, one of the error codes below may appear on your tankless water heater.

01. Displays the “E1” Error Code

The “E1” error code on the Ecosmart water heater’s display indicates that the inlet thermistor is not working properly or is reading the temperature incorrectly. Here are some common reasons to show this code,

  • If water can’t flow smoothly
  • The round knob is not placed correctly
  • The LED display is unable to read CE1
  • Turning the LED display off

How To Fix:

If your Ecosmart water heater is showing the “E1” error code, it is best to switch to a different temperature. However, you can follow the steps below to solve the issue temporarily:

  • Turn the LED display on (If it is off) and leave it running 
  • For the LED display to recognize the problem, turn on the water
  • Press the circular knob for 3 to 5 seconds, then let go
  • Run the water for 3 to 4 minutes, then check whether it is warm enough or not

02. Displays the “E2” Error Code

Your water heater may show the “E2” error code from time to time. It is an indication that there is something wrong with the thermistor. This type of code shows when the outlet thermistors are unable to read the temperature correctly. Hence, the prime suspect for displaying such a code is faulty thermistors. 

How To Fix:

Since the problem is caused by faulty thermistors, the simple way to fix this issue is to change the outlet thermistor permanently. Additionally, you can temporarily fix it by resetting the EcoSmart tankless water heater.  

03. Displays the “E3” Error Code

This type of error code may appear when not only the inlet thermistor but also the outlet one fails to read the temperature of the water correctly. So, it is almost similar to showing the “E2” error code, except this time, both thermistors are unable to read water temperature. 

How To Fix:

You need to replace both the outlet and inlet thermistors to solve this issue. However, it can be difficult to replace them both at the same time. Therefore, you can try resetting the water heater for a temporary fix. 

04. Displays The “E4” Error Code

Sometimes, the high temperature of the water can be responsible for causing your EcoSmart water heater to malfunction. The “E4” error code may pop up when the water temperature is 150 °F or higher. 

Around 2 to 4 thermostats are equipped with almost all tankless water heaters. Each of these thermostats is rated at 140 °F. As a result, you will likely get this code when the water temperature is much higher than 140 °F.

How To Fix:

Fixing this issue is simple. All you need to do is make sure the water temperature does not go beyond 140 °F.     

05. Displays The “E5” Error Code

Just like the “E1” code, the Ecosmart water heater may display an “E5” error code. It means the current flow of water is too high. The following can be the culprits showing this type of code,

  • The valve is too tight for the incoming and outgoing water
  • Too much water is flowing
  • The round knob won’t turn in the right direction  

How To Fix:

The water heater must include an aerator to regulate the enormous amount of water. However, you may also use the following alternatives to assist you to resolve the issue,

  • To regulate or reduce the flow of water in the tub, sink, or shower, use an aerator. For each of them adjust the flow rate accordingly,
    • Washing machines: 1.5-2.5 gallons/minute
    • Bathtubs: 3.5-8 gallons/minute
    • Sinks: 1-2.5 gallons/minute
    • Showers: 1.5-3 gallons/minute
  • The flow of water to the system from the main valve should be moved more slowly
  • To regulate the water flow, install a flow restrictor that is only slightly closed
  • Ensure that the circular knob is turned clockwise

Whatever the problem is, you need to know how to troubleshoot your EcoSmart water heater. With proper troubleshooting, you can fix minor issues and keep the heater in a stable condition. Watch the video to get a better insight to troubleshoot an Ecosmart tankless water heater,


There might be some questions going through your mind regarding the EcoSmart water heater issues. We hope the following are some of them:

How long does an EcoSmart water heater last?

Tankless EcoSmart water heaters are known for their long lifespans. Typically, these heaters can last for more than 20 years if used properly. This is longer than other types of water heaters. On top of that, EcoSmart heaters come with limited lifetime warranties, making them more reliable. 

Do tankless water heaters need high maintenance?

No, tankless water heaters don’t require high maintenance. You should service this type of water heater at least once a year. Also, the service might be included in the typical preventative maintenance that a heating and cooling system would get.

What country manufactures EcoSmart water heaters?

Basically, EcoSmart water heaters are made in Atlanta and Waterbury. Therefore, these water heaters are reliable choices for US citizens who are looking for heating solutions for industrial, commercial, or residential purposes.

Are there any disadvantages to tankless water heaters?

Apart from the issues, tankless water heaters have some drawbacks. For instance, you may need proper skills to install this type of water heater. Moreover, the upfront cost of this water heater is high, and the flow rate is limited.  

Do tankless water heaters make loud noises?

Yes, tankless water heaters tend to create noise while turning on and heating water. However, the noise is not too loud, it is rather tolerable. As a result, you don’t need to be concerned about this. 


EcoSmart water heater problems can be quickly solved with the right approach, whether it is a simple or complex issue. So, whenever you encounter any issues with EcoSmart tankless water heater,  just follow our guide and fix it by yourself. 

Don’t hesitate to leave a comment below if you have any queries. We will be happy to help you.

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6 thoughts on “EcoSmart Water Heater Problems [7 Easy Solutions]”

  1. Problems with flow sensor, this is my second senor to be replaced. Eco smart 27 started make ng rattling noises. Same problem when the first went up and damages element. Cold water inlet pipe bursted.

    • Hi Runin1wild

      Your water heater needs a physical check-up to find out the reason for sensor failure. It would be wise to take help from the EcoSmart customer support center.

      Wish you all the best.

        • Hi Donald

          You are facing water temperature issues due to one or more reasons like a broken dip tube, a faulty element, a thermostat, or a blocked exhaust.

          Well, to fix the problem, inspect all the issues one by one & try to find out the main reason behind the issue & fix it. Plus, make sure the exhaust pipe is open & the vents are clear. Also, ensure the system is installed correctly.

          Hopefully, your water heater problem will be solved.

          Best of luck!

    • Hi Sheila

      Generally, an EcoSmart water heater produces a popping sound due to scale & sediment buildup inside the tank. Plus, this sediment can form a thin layer of dirt on the bottom of the tank.

      And your water heater stops heating water may be due to one or more reasons like a faulty heating element, crossed wires, too high flow rate, or the voltage is less than 240V.

      Well, to fix the water heater issue, it would be wise to contact the Ecosmart customer support center or your local Ecosmart dealer.

      Best of luck!


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