Water temperature fluctuates between hot and cold during use.

Safety: Beware of sudden hot water surges that can cause scalding.

• 1. Check plumbing stability: Ensure no other large water consumers (e.g., washing machine) are causing big pressure swings on the same line.
• 2. Clean filters and aerators: Clean the heater’s inlet filter and any faucet aerators or shower heads to stabilize flow.
• 3. Inspect sensors: Check inlet and outlet NTC sensors for secure mounting and good wiring connections. Replace any sensor with erratic resistance readings.
• 4. Flow sensor: Clean or replace the flow sensor if its signal is intermittent, as this directly affects power modulation.