In this manual it tell you what to look for. https://db.tt/dB1dcAve
Thanks for the manual. It says the following about this error:
Description: High temperature Heating error. HE1.
Suspect: Heater relay. Main PCB. Thermistor.
Technical Description: Water temperature sensed above 176F during operation. Possible defect : Thermistor error, Main PBA or shorted heater relay.
What are the next steps I should take?