E08
Lochinvar
Inlet Water Temperature Sensor Fault (Open/Short)
Heater shows E08; unit will not run and may indicate an inlet water temperature sensor problem.
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Failed inlet temperature sensor, Loose or corroded sensor connector, Damaged wiring harness
How to Fix / Troubleshooting
Safety: Disconnect power before working inside the heater.
Steps:
- Locate inlet sensor: Find the inlet water temperature sensor on the inlet header or manifold.
- Inspect connections: Ensure the sensor is firmly threaded into the header and the wiring connector is tight and clean.
- Test sensor: With power off, disconnect the sensor and measure resistance with a multimeter. Compare to Lochinvar's NTC chart. Replace if readings are out of specification.
- Check harness: Follow the harness back to the control board, looking for pinched or burned sections. Repair or replace as needed.
After replacing the sensor, clear the error by cycling power and verify normal operation.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Inlet Water Temperature Sensor
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements