Eccotemp Systems 40H User manual

40 Model Comprehensive
Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
Listed below are some common questions and troubleshooting guidelines for our 40H/HI water heaters. Always remember
when working on a particular issue to ensure that the water heater is unplugged and the gas is shut off. Always seek
professional advice and assistance, if needed. Also, you are welcome to call Technical Support at 866-356-1992 or, for
fastest service, submit a support ticket by going to www.eccotemp.comand clicking on the “Support,” tab on the right side
of the page.
Basic Information:
The 40H and 40HI are gas powered tankless water heaters. After setting them to the desired temperature, they will self
adjust, based upon water flow, to maintain a desired temperature. They are designed for residential use for a 2 bath, 3
bedroom home. Though capable of achieving higher temperatures, it is recommended that you set the temperature at 120
degrees Fahrenheit or below.
General Questions:
Questions:
Q. I want to mount inside my camper or food truck?
A. Remember, the 40H and 40HI were designed for residential, not commercial, use. The 40HI is made to be mounted
indoors. However, DOT Regulations state that you cannot have a tankless water heater hooked to a gas supply line while
in motion. Once stationary, you can then hook up the gas supply and use your 40 model water heater.
Q. Can I use a 40H or 40HI with a portable propane tank and rubber hose?
A. Trying to use a 40H or 40 HI in this way will not meet building code, will reduce performance, can result in gas related
error codes, or damage to the water heater.
Q. Will it work on a 12v supply pump?
A. Yes, as long as your pump is capable of providing adequate water flow and water pressure. The 40 model water
heaters need a minimum of ¾GPM and 20PSI to operate.
Q. Can I use the 40H or 40HI with my existing plumbing?
A. The water heater has ½” NPT fittings so it is easily plumbed in to existing lines.
Q. Can I use this water heater to heat my swimming pool or hot tub?
A. You can use an 40H or 40HI to generate hot water for any application. Attempting to use it with a recirculation system
for an application like this will void your warranty and permanently damage your water heater.
Q. Can I use to this water heater in a recirculation system at all?
A. No, this will void your warranty and permanently damage your water heater.
Q. What size venting do I need for a 40HI?
A. The 40HI requires 3” Cat II/III stainless steel venting. Please check your local building code.

40 Model Comprehensive
Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
Thank you for contacting Eccotemp Systems Help Desk. Our goal is to provide you with the best customer service
possible.
If your 40H/HI has been working fine but is now having issues, ask yourself this question: What has changed?
There are a few basic things which can affect the operation of a tankless water heater, which are listed below.
1. Clogged filter screens
2. Low water flow
3. Single knob faucets
4. Incorrect gas type or gas pressure
5. Low or empty gas tanks
6. Issues with the electrical supply
7. Recent power surges (i.e. lightning)
8. High temperature setting
9. Blockage in the exhaust
If any of these things seem possible, then please check to see if it applies through troubleshooting prior to calling
customer service.
The first and most important thing to do is to make sure the gas being supplied to the water heater is correct for
your model. There is a plate on the side of the water heater which will provide the gas type that it was designed to
be used with. This plate will either say NG for Natural Gas or LP for Liquid Propane. Do not run your water heater
with the incorrect gas type.
Make sure the temperature is set to 120 degrees or below. The 40H/HI will overheat with low water flow. If this is
happening, remove any filter screens that are installed in your faucets and see if that alleviates your problem.
40H/HI is experiencing issues, but only at one faucet:
Is there anything different between this faucet and the other fixtures that are working properly? Usually this is attributed to
too little or too much water flow. Specifically if the water heater is overheating or shutting down during operation, check the
filter screen in your faucet and free up your water flow as much as possible. This can also be directly related to the faucet
being a single knob faucet. Again, free up your water flow as much as possible.
40H/HI will not turn on and doesn’t have anything on the display:
If your water heater does not show anything on the display and will not run, you most likely have an electrical issue. Check
to make sure that the main breaker supplying power to the outlet is not tripped. Also, if the power outlet that your water
heater is plugged into has an incorporated breaker, make sure that it is not tripped. A very easy way to test to make sure
the outlet is working correctly is to plug a different electrical appliance into it and see if it will turn on.

40 Model Comprehensive
Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
After verifying that your water heater has power going to it, you can check the internal wire connections. First, unplug
your water heater from the electrical outlet. After doing so, remove the cover by taking out the four screws on the front
which hold it in place. On the indoor models the digital display is attached to the cover, so please be careful as to not
damage the connections. Once the cover has been removed, check the wire connections throughout the water heater to
make sure everything is plugged up and secure. If it looks like there is a build-up of corrosion, unplugging and re-
plugging the connections verify they are correct. Note: the computers are interchangeable between the indoor and
outdoor models. The main difference is that the indoor models connect directly to the computer board and the outdoor
models connect to a set of green wires coming from the computer board. On the 40HI, there will be a green wire that is
not connected to anything and on the 40H there will be a wide white ribbon wire that is not connected to anything. This
is perfectly normal.
Lastly, if you then test your water heater and it does still will not come on, you will need to remove the computer board
and check to make sure the fuses are intact. Again, make sure that you have unplugged the power cord so there is no
electricity going to it. Inside, there is a grey box that is located near the top right. Remove the two screws from the front
of the board and it will slide out freely. On the computer board you will see two rubber boots which cover and protect the
fuses. Pull these boots off and, if the fuses are still in working order, there will be a thin wire that is visible inside of them
and should not be broken. If the wire is broken, you will need to replace the fuse.
If these steps do not fix your issue, please call technical support at 866-356-1992.
40H/HI is displaying set temperature, but will not come on:
This means that your water heater is not seeing that there is water flowing through it. The most common reason for this
is low water flow. To determine if this is the case, turn on two faucets and see if your system turns on. If this works, you
probably have clogged filter screens. Check all of the filter screens in your faucets to see if they have become clogged
over time. If you remove the filter screen from a faucet, turn on the hot water at that location, and the system runs, you
can always just not reinstall the screen and use the faucet in this manner. Next, check the filter screen that is in the
water heater itself. There is a drain plug where the inlet water pipe enters the water heater. There is a screw located on
the front of the plug, inside of it. Do not try to loosen or tighten this screw. The entire drain plug will unscrew and can be
removed. Once removed, you will see a filter screen with a magnet in the center of it. If dirty, they can both be cleaned
by gently using a wire brush. If you need a new filter screen, you can order one from our website at
www.eccotemp.com.
Lastly, you will need to check your flow sensor to verify that it is working properly. Go to the 40H and 40HI
Troubleshooting section on the forums page. This is located at https://eccotemp.zendesk.com/forums.You will find a
Flow Sensor Installation Guide which will help in completing this task. Follow the instructions in the guide to remove the
flow sensor. Once removed, you can blow through the flow sensor to verify that the impeller inside of it is spinning freely
and there is no debris inside of it. Reinstall the flow sensor as the guide instructs and test the water heater.
If these steps do not work, please contact technical support at 866-356-1992.

40 Model Comprehensive
Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
40H is showing two rotating squares:
This means that the water heater has been turned off either by pushing the power button or the power was lost somehow
while it was running. This can be resolved by simply turning the water heater back on with the remote.
If this does not fix your issue, please contact technical support at 866-356-1992.
Description of Error Codes:
E0:
The E0 error code pertains to the outgoing water temperature sensor.
This can typically be corrected by verifying the connection of this sensor with the computer board. To do this, unplug the
water heater from the electrical outlet and remove the cover by unscrewing the four screws that hold it in place. After
doing so, find the connection to the computer board, unplug the connector, and reconnect it. You can now plug the water
heater back and attempt to run it as usual.
If this does not fix your issue, please contact technical support at 866-356-1992 as it may be necessary to replace your
sensor.

FVI12 Comprehensive Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
E1:
An E1 is directly related to an issue involving your gas supply.
If you are getting an E1 error code, first verify that your water heater is the correct gas type. On the right side of the water
heater, there is a plate that specifies LP for Liquid Propane or NG for Natural Gas. This should match the type of gas that
is being supplied. If this matches, verify that your installer checked to make sure that the gas is the correct pressure for
your 40H/HI. The pressure needed for this model is 11 inches of water column for Liquid Propane and 8 inches of water
column for Natural Gas. Also, make sure your installer used a regulator capable of delivering the proper gas flow needed
for the 133,000BTU 40H/HI. Next, verify that your gas supply is turned on. Lastly, after doing all of this, make sure that
you are not out of gas.
If these steps do not fix your issue, please contact technical support at 866-356-1992. Prior to calling, please be in front
of the water heater so we can troubleshoot over the phone. If you can’t be in front of the water heater, please be prepared
to answer these questions:
Can you hear the water heater trying to ignite? In a proper ignition sequence, the fan will come on, the display will show
ground water temperature, and you will hear a series of fast, high pitched clicking followed by a few lower pitched clicks
which are noticeably slower. It should go through this sequence twice if it does not ignite.
Does the water heater ignite, run briefly, and then shut itself down?
E2
An E2 error code indicates that there is something occurring electrically, within the water heater.
A common solution for this is to first unplug the water heater from its electrical supply. Next, remove the cover by
unscrewing the four screws that hold it in place. The indoor mounted 40HI models have a ribbon cable connecting the
display to the computer board. Please be careful as to not damage this wire. You will need to disconnect it using the
black connector located 6 inches from the display itself.
Once inside the water heater, you will see a grey box which contains the computer board located on the right side. If you
remove the two screws on the face of the computer board, it will slide out freely from the box. Next, disconnect and
reconnect all of the wires which are connected to the computer board to verify that everything is seated properly. You can
then screw the computer board back in place, replace the cover, plug up the power supply, and attempt to run the water
heater as normal.
If this does not fix your issue, please contact technical support at 866-356-1992

FVI12 Comprehensive Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
E3
An E3 Error indicates that the water heater has overheated, meaning it reached very high temperatures and shut itself
down so as not to cause damage or harm.
The reason a 40H/HI can overheat is because the temperature is set too high, the water flow is too low, or a combination of
the two factors. If your temperature is set higher than 120F, set the water heater to 120F and try to operate it as usual.
Lastly, if this is specific to one or two faucets only, check the filter screens in the faucets and free up your water flow as
much as possible.
If your water heater is going directly to an E3 and not trying to ignite, or if the steps listed above do not fix your issue,
please contact technical support at 866-356-1992.
E5
An E5 error code indicates that there is an issue with your fan or venting.
If your fan is coming on, but then giving you an E5, you most likely have a blockage in your venting. This mostly pertains to
the 40HI as the 40H models vent directly out of the front of the heater. Check inside of your vent pipe to make sure there is
no debris blocking the flow of air.
If your fan is not coming on, then you have an issue with voltage or there is something that is not allowing the fan to spin
freely. A common solution for this is to first unplug the water heater from its electrical supply. Next, remove the cover by
unscrewing the four screws that hold it in place. The indoor mounted 40HI models have a ribbon cable connecting the
display to the computer board. Please be careful as to not damage this wire. You will need to disconnect it using the black
connector located 6 inches from the display itself.

FVI12 Comprehensive Troubleshooting Guide
Eccotemp Systems, LLC
315a Industrial Rd. Summerville, SC 29483
www.eccotemp.com
1-866-356-1992
Inside the water heater, at the bottom left, you will see the fan. Again, with the water heater unplugged, reach in and spin
the inside of the fan to make sure that it spins freely. After doing so, on the right side of the water heater, you will see a
grey box which contains the computer board located on the right side. If you remove the two screws on the face of the
computer board, it will slide out freely from the box. Next, disconnect and reconnect all of the wires which are connected
to the computer board to verify that everything is seated properly. Lastly, you will see two blue rubber boots on the
computer board. Remove the rubber boot from the fuse closest to the middle of the board and check to make sure it is
still intact. If it is not intact (the small metal wire in the center of it is broken), replace the fuse. Then, reinstall the board,
replace the cover, plug up the water heater to its power supply, and see if your issue is resolved.
If these steps do not fix your issue, please contact technical support at 866-356-1992.
E6
An E6 is extremely rare and is caused by the water heater not being able to maintain temperature, but not overheating.
This can be due to a low temperature setting, low water low, a higher than normal ground water temperature, or a
combination of the three. Increasing your water flow should fix this.
If these steps do not fix your issue, please contact technical support at 866-356-1992.