Troubleshooting 40H & 40HI

This section will trouble shoot the 40H (outdoor) and the 40HI (indoor) most common questions and Error Codes.

First thing to do is make sure the gas type is proper for your application. Then UNPLUG
UNIT FROM WALL, take the cover off and check all wire connections, make sure all wires are connected. Note the computers are interchangeable from indoor to outdoor. With
that in mind, on the indoor unit there is a green wire that will not be connected to anything; as well the outdoor unit will have a wide white set of wires that are not connected to anything.

Make sure temperature is set to 120 degrees or below!

If there is no error code and the unit does not come on when the HOT water is turned on.

This means that the flow meter is not sending a signal to the computer which starts the machine. 1st to fix this you want to locate the flow meter at the bottom right, it has red black and yellow wires coming out of a black sensor that is screwed to the flow meter. 2nd check the wire connection; follow the wires to where it connects to the computer. If both were connected you will want to remove the flow meter. There are four screws that hold this
meter in place; two that you can see; one at the top, and one at the bottom of the flow
meter, and two on the outside of the cabinet that hold the inlet pipe in place. Blow thru the
meter it should make a zing sound when the little fan inside spins. Reinsert the flow meter
and turn hot water on.

If the display shows two squares rotating up and down. This pertains to the 40H only.

1st push the power button. 2nd If the unit has been in operation for a while and all of the sudden the squares begin rotating. This means power was lost somehow while unit was running. 3rd The flow meter wire is loose on the computer, or the connector where the two wires connect between the computer and the flow meter are loose. 4th The remote itself may have a short, or the power cord going to the computer one of the prongs may not be making a good connection threw the connector or the computer.

Error Codes: Regardless of what the error code is; take the two front screws out of the computer board and it will slide out. Pull the inserts that are lined up along the front of that board and put them back in one by one. Plug the unit back in and see if this solves any issues.

E0: wire coming out of this sensor that leads to the computer board Temperature sensor has lost connection or needs to be replaced. You can locate this sensor at the bottom left; it is screwed into the outgoing (hot) water pipe. There is a white wire that leads up to the
computer from that sensor.

E1: Gas is not set to 11 inches of water column if using Propane or 7 inches if using Natural Gas. Another possibility; there is not a minimum of ¾ of a gallon of water flowing thru the unit. Or there is not a ¾ gas line

E2: The thermocouple is not reading the flame. The temperature is set above 120 degrees and has damaged the thermocouple. Or the connection has been lost. If pulling the circuits
from the computer board and putting them back in did not fix the issue; the thermocouple
needs to be replaced.

E3: Overheating protection. Turn the temp down to 120 or below. If this does not fix the
issue UNPLUG UNIT FROM WALL. The over temperature sensor and or the fusible link may
need to be replaced. To check the sensor; take the cover off and look at the top right side you will see a circular sensor on an elbow (pipe); it has a blue rubber boot on one end and a white cover on the other side. You want to take the ends off of the sensor and touch them together. If that does not temporarily fix the issue until we can get that part out to you there is a possibility it is the fusible link. To override this you want to take the blue booted wire and look to the right side of the computer (grey rectangular box top right) you will see another blue boot attached to a wire that wraps around the copper heat exchanger. You want to touch the two blue connectors together. If this doesnot give a temporary fix; it could have damaged the computer board from being set above 120 degrees.

E5: Unplug unit. First thing to do is check the fuse. This is inside the computer (gray
rectangular box at top right). There are two screws on the front of this box; remove those
and the computer will slide out. Look at the blue rubber boot next to a coiled copper wire;
pull the blue boot off and you will have to look very close at the fuse the wire is very small. 2nd thing is to follow the fan wire to the computer and make sure that the wires inside the
connectors are all in line and at the same level. You want to do the same with the transformer wires. This connector is going to be the largest one on the computer board.

E6: This means that there is not a minimum of ¾ of a gallon running thru the machine. Or the temperature is set so low that the unit is not using the minimum amount of gas needed which are twenty thousand BTUs to start.

IF YOU ARE NOT COMFORTABLE OPERATING ON THE UNIT OR NEED FURTHER ASSISTANCE PLEASE EMAIL tech@eccotemp.com OR CALL 866-356-1992.