Eternal Water Heater Error Codes

In 2014 increasing problems with the Eternal heat exchanger and controls resulted in leaks and premature system failures. After a year of trying to correct the problems, Grand Hall, the parent company of Eternal Water Heaters, ceased operations in North America leaving their customers without warranty coverage, part replacements and technical resources.

You may be able to clear the Error Message simply by turning the hot water tap OFF, then ON again. If this does not clear the Error Message, try pushing the ON/OFF button OFF, then ON again. If the Error Message still remains, contact Hot Water Now! and arrange for a service call.

Eternal Hybrid Water Heaters

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Eternal Water Heater Repair

In some cases, we have the parts to make successful repairs. We are generally able to service and repair units that are not working properly, or are displaying an error code. Once the units develop a leak it’s time to consider replacing the system.

Self Monitoring

To assist with diagnosing an error, Eternal tankless water heaters have the ability to check their own operation continuously. If an error occurs, a message will flash on the digital monitor of the front panel. Please refer to the error code when scheduling service.

We have technicians available today for a diagnostic visit or prepare an estimate to replace your existing tankless. Call 720-934-8711, or click here today.

Hot Water Now! Is licensed and insured. Our Colorado plumbing license number is PC.0003145.

Eternal FAQ's

Eternal Water Heater Frequently Asked Service and Repair Questions

Burner does not ignite when the hot water is opened.

  1. Make sure that the ON/OFF button on the front or remote controller has been turned ON.
  2. If the monitor on the front or remote controller is blank, make sure the power cord is plugged in and the 3A fuses on the main controller in the unit are good.
  3. Make sure water is flowing to the unit. The unit activates once the inlet water flow is over 0.5 gpm.
  4. Make sure the cold and hot water lines are not plumbed in the wrong locations.
  5. Make sure that the water lines are not frozen.
  6. Make sure that the cold water and gas supply lines are opened.

Water is not hot enough.

  1. Check the setting temperature on the unit is not too low.
  2. Make sure that the filter in the cold water supply line is not clogged with debris.
  3. Make sure that the gas supply type is correct.
  4. Check the supply and manifold gas pressures are in accordance with specifications.
  5. Make sure that the water flow sensor with three wires has been properly connected.

Water is too hot.

  1. Make sure that the setting temperature on the unit is not too hot.
  2. Make sure that the filter in the cold water supply line is not clogged with debris.
  3. Make sure that the gas supply type is correct.

Hot water temperature fluctuates at the opened tap.

  1. Make sure the filter in the cold water supply line is clean.
  2. Make sure that the gas supply type is correct.
  3. Check the supply gas pressure is sufficient.

Abnormal sounds come from unit during operation.

  1. A leak of combustion gas between sealed chamber and exhaust tube inside the unit.
  2. Improper venting termination, make sure that the venting termination complies with specifications.
  3. Make sure the supply gas pressure is sufficient. Insufficient gas pressure will cause unstable burner flame and noise.

The blower is still operating after the combustion stops.

  1. This is normal because the blower still keeps operating for 1 minute to exhaust the flue gas from the chamber once the combustion has stopped.

I can't change the setting temperature to above 140°F on the front controller.

  1. This is a safety device to prevent scalding. Hot water temperature over 125°F can cause severe burns instantly or death.
Eternal tankless water heater replacement with Rinnai tankless unit.
Hot Water Now! Is licensed and insured. Our Colorado plumbing license number is PC.0003145.
Eternal Water Heater Schematic

Eternal Tankless Error Codes

To assist with diagnosing an error, Eternal tankless water heaters have the ability to check their own operation continuously. If an error occurs, a message will flash on the digital monitor of the front panel. Please refer to the error code when scheduling service (720) 934-8711.

Code Display Cause Remedy
E1 Remaining flame detected Call Hot Water Now! (720) 934-8711
E2 Ignition failure - doesn't detect flame signal Check gas line, ignitor, flame rod
Check wire connection of 8p wire and ignitor wire
Check ignition noise
Check gas type and manifold pressure
E3 Abnormal combustion - after detection of flame signal, system lose the signal Check the gas supply in enough
Check the gas valve
Check wire connection of 8p wire and ignitor wire
Check gas type and pressure are correct
Check power supply for proper voltage
E4 An outlet thermistor open Check the outlet thermistor
Check wire connection of 14p wire and thermistor wire
E5 An outlet thermistor short Check the outlet thermistor
Check wire connection of 14p wire and thermistor wire
E6 A H/E thermistor open Check the H/E thermistor
Check wire connection of 14p wire and thermistor wire
E7 A H/E thermistor short Check the H/E thermistor
Check wire connection of 14p wire and thermistor wire
E8 An inlet thermistor open Check the inlet thermistor
Check wire connection of 14p wire and thermistor wire
E9 An inlet thermistor short Check the inlet thermistor
Check wire connection of 14p wire and thermistor wire
E11 A DC motor failure Check DC motor
Check wire connection of 6p wire
E13 No filled water in tank or pressure switch failure Check the water filled in tank
Check water pressure switch
Check connection of 14p wire and water pressure wire
E23 Adjust control valve is not connected Check the adjust control valve movement noise
Check wire connection of 16p wire and adjust valve wire
E24 Mixing control valve is not connected Check the mixing control valve movement noise
Check wire connection of 16p wire and mixing valve wire
E26 Adjust control valve initialization failure Check the adjust control valve movement noise
Check wire connection of 16p wire and adjust valve wire
E27 Mixing control valve initialization failure Check the mixing control valve movement noise
Check wire connection of 16p wire and mixing valve wire
E28 Power line of main gas valve is open Check the thermostat
Check the thermal fuse
Check the air pressure switch
Check wire connection of gas valve, thermostat, thermal fuse and air pressure switch
E30 Rotation of a DC fan is too high Call Hot Water Now! (720) 934-8711
E31 Rotation of a DC fan is too low Call Hot Water Now! (720) 934-8711
E36 A controller failure concerning gas valve Call Hot Water Now! (720) 934-8711
E37 Communication failure with SUB CPU Call Hot Water Now! (720) 934-8711
E38 Subsidiary RAM failure Call Hot Water Now! (720) 934-8711
E39 A controller failure concerning Subsidiary flame signal Call Hot Water Now! (720) 934-8711
E40 Main RAM failure Call Hot Water Now! (720) 934-8711
E41 A controller failure concerning flame signal Call Hot Water Now! (720) 934-8711
E42 Main ROM failure Call Hot Water Now! (720) 934-8711
E43 Main MUX error Call Hot Water Now! (720) 934-8711
E47 Intake Thermistor Short Check the intake thermistor
Check wire connection of 14p wire and thermistor wire
E48 Intake Thermistor Open Check the intake thermistor
Check wire connection of 14p wire and thermistor wire
E49 Intake Thermistor Detect Abnormal Situation Call Hot Water Now! (720) 934-8711
E50 Room A Thermistor Short (only hydro heating) Check the room A thermistor
Check wire connection of 12p wire and thermistor wire
E51 Room A Thermistor Open (only hydro heating) Check the room A thermistor
Check wire connection of 12p wire and thermistor wire
E52 Room B Thermistor Short (only hydro heating) Check the room B thermistor
Check wire connection of 12p wire and thermistor wire
E53 Room B Thermistor Open (only hydro heating) Check the room B thermistor
Check wire connection of 12p wire and thermistor wire
E54 Current Leak on Gas Valve Power Check gas valve
Check connection of gas valve wire
E56 Less than 0.3gpm of water flow at recirculation mode and hydro heating Check flow sensor
Check recirculation pump and loop
Check connection of 14p wire and flow sensor wire
E57 Pump is not connected Check wire connection of 8p wire and pump wire
Check the pump
E58 / E59 No response from ICC module Call Hot Water Now! (720) 934-8711
E93 Master can't have any data on CAN line Check connection of 3p wire and MCU wire
Check connection of termination wire and resistor(120Ω)
E94 Sub can't have any signal from master Check connection of 3p wire and MCU wire
Check connection of termination wire and resistor(120Ω)
Hot Water Now! Is licensed and insured. Our Colorado plumbing license number is PC.0003145.
Eternal tankless water heater schematic

Click on Image for Larger View

Eternal tankless water heater schematic

Click on Image for Larger View


Parts List for Model GU145(S)
KEY DESCRIPTION

  • 1. Panel, Front Assembly
  • 2. Panel, Top / Rear Assembly
  • 3. Panel, Rear
  • 4. Panel, Left Assembly
  • 5. Panel, Right Assembly (GU145(S))
  • 6. Panel, Bottom
  • 7. Mounting Bracket
  • 8. Wall Bracket
  • 9. Controller / Front
  • 10. T&P Relief Valve (Cash Acme)
  • 11. Vent Collar
  • 12. Vent Collar Packing
  • 13. Rubber Foot
  • 14. Drain Valve Assembly
  • 15. Main Power Cord
  • 16. Handle
  • 17. Condensing Nipple
  • 18. Mesh Screen
  • 19. Outdoor Venting Cap (Optional)
  • 20. Trap Cleaner Assembly
  • 21. Radial Blower Assembly
  • 22. Gas Valve
  • 23. Air Pressure Switch (GU145(S))
  • 24. Burner Assembly
  • 25. Main Controller (GU145(S))
  • 26. Cold Water Tube Assembly (GU145(S))
  • 27. Hot Water Tube Assembly (GU145(S))
  • 28. Flexible Silencer Kit
  • 29. Mixing Valve
  • 30. EC Adapter
  • 31. Water Pressure Switch

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