Maintenance Guides / Plumbing & Water

Flush tankless water heater

Difficulty: moderateTime: 90 minsEst. Cost: $15 - $40

Why it matters

Mineral deposits (scale) build up on the heat exchanger in hard water areas, reducing efficiency and eventually causing the unit to error out. Annual flushing keeps it running at full capacity.

Stop forgetting to do this.

HomeOS generates a personalized maintenance schedule so you never miss another flush tankless water heater.

How to do it

  • 1

    Turn off the heater and shut the gas/electric supply.

  • 2

    Close the water isolation valves.

  • 3

    Connect a descaling pump and hose (or use the descaling kit).

  • 4

    Circulate white vinegar for 45–60 minutes.

  • 5

    Flush with fresh water.

  • 6

    Restore normal operation.