Display shows E5 and unit does not heat; may appear intermittently when demand is high.

Safety: Turn OFF the breaker and verify power is off. This fault involves high current circuits; use extreme caution.

• Inspect wiring: Remove the front cover. Check the main power lugs, element terminals, and bus bars for discoloration, melted insulation, or loose screws. Tighten loose connections to manufacturer torque specs with power OFF.
• Check heating elements: With a multimeter set to resistance, disconnect each heating element and measure resistance between its terminals and from each terminal to ground. A very low resistance or continuity to ground indicates a shorted element that must be replaced.
• Verify supply wiring: Confirm that the breaker size and wire gauge match EcoSmart’s installation requirements. Undersized wiring can overheat and cause nuisance overcurrent faults.
• Reset and test: After correcting any wiring or replacing a bad element, reassemble, restore power, and run hot water while monitoring for E5.
• Professional service: If elements and wiring test good, the internal current sensing circuit or control board may be defective. This should be diagnosed and replaced by a qualified technician.