A certified Debard Plumbing technician will inspect all components, flush the heat exchanger, clean control compartments, burners, and air circulating passageways. We will also inspect the vent system for blockages or damage and clean the inlet water filter. The procedure takes less than an hour. Flushing your tankless water heater once a year is the most important maintenance practice for optimal performance, warranty adherence, and can help extend its lifespan for many years. When scale buildup in the heat exchanger begins to affect the performance of the water heater a diagnostic code "LC#" will display on the temperature control panel.