Heater indicator flashing, solution not heating, E8 displayed

Safety: Unplug and allow the machine to cool completely before working on the heater. Risk of electric shock and burns.

• Confirm symptom:
  • Cold solution at the wand despite heater being enabled and E8 on display.
• Inspect heater connections:
  • Locate the in-line solution heater module (usually a metal or plastic block in the solution line).
  • Check spade connectors and wiring harness for burning or looseness.
• Test heater element:
  • Disconnect heater from the circuit.
  • Measure resistance across heater terminals; open circuit indicates a failed heater element.
• Check thermal fuse and thermostat:
  • Many Henry heaters include a non-resettable thermal fuse and a thermostat.
  • Test continuity; replace the heater assembly if either is open and not serviceable separately.
• Inspect control PCB:
  • If heater tests good, the fault may be on the control PCB (heater relay or triac).
  • Look for burnt tracks or components; replace PCB if damaged.