How often should I flush my tankless water heater

I’ve been reading mixed opinions on the right frequency for flushing tankless water heaters — some say once a year is enough, while others recommend every six months, especially in areas with hard water. What have you all found works best for maintaining efficiency and longevity?

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I’ve found that flushing every six months works best, especially with hard water. You’ll be surprised at how much sediment accumulates over time. Just make sure to use a good descaling solution like vinegar or a specific flush kit — you’ll feel the difference in efficiency.

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this drives me nuts too… I’ve noticed that flushing once a year might leave too much sediment if you’re in a hard water area. Maybe try a good descaling solution when you do it — that can help with buildup.

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Flushing every six months has worked well for me, especially in areas prone to buildup; i usually follow it up with a quick inspection of the filters, just to make sure everything’s functioning smoothly. Have you considered a specific descaler, or are you just planning to use vinegar?

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@jmartin65, I’ve noticed that the type of descaler you use can really affect how well it cleans out the sediment… A good citric acid-based one worked wonders for me last time. Which products have you tried in the past?

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