To Clean Or Not To Clean Tankless Water Heater

[aln]

I have 2 tankless water heaters (in different locations), a Navien and a Rinnai. Both manufacturers recommend they be cleaned annually to remove mineral deposits. In both locations, I also have water softeners, and I have been told that with water softeners, I don't need to do the cleaning since they already remove the minerals before the water gets to the heater. I would very much appreciate your thoughts on that.
Thanks
Al

 

[GReynolds929]

I have 2 tankless water heaters (in different locations), a Navien and a Rinnai. Both manufacturers recommend they be cleaned annually to remove mineral deposits. In both locations, I also have water softeners, and I have been told that with water softeners, I don't need to do the cleaning since they already remove the minerals before the water gets to the heater. I would very much appreciate your thoughts on that.
Thanks
Al

If they're not flushed annually the warranty is usually voided.

 

[edfiero]

I used a tankless for about 8 years without a 'cleaning' and never had any issues. Then I did the recommended cleaning procedure, but didn't notice any difference afterwards. I can't say if it did any good or not. I would imagine that the condition of the water has a lot to do with whether or not you need to clean.

 

[aln]

If they're not flushed annually the warranty is usually voided.

Thanks. I'll have to check that out.

 

[aln]

I used a tankless for about 8 years without a 'cleaning' and never had any issues. Then I did the recommended cleaning procedure, but didn't notice any difference afterwards. I can't say if it did any good or not. I would imagine that the condition of the water has a lot to do with whether or not you need to clean.

Thanks. I'm sure it has to do with the condition of the water. I'm just wondering if the water softener corrects any "bad" condition so that the flushing is not required.

 

[Jeff Handy]

Even softened water has minerals still in it.
Follow the flushing guidelines.

 

[Mitchell-DIY-Guy]

Even softened water has minerals still in it.
Follow the flushing guidelines.

Absolutely. Water softening merely exchanges sodium ions (from common salt) for the "hardness" ions of calcium and magnesium.

What that means is this: if your natural water is 10 grains of hardness, and you soften it, those 10 grains of magnesium and calcium are "swapped" for sodium. If your natural water is 30 grains of hardness...well, yes that's right. You have three times the amount of sodium.

While "sodium" laden water behaves and tastes different that that full of calcium and magnesium, it's still a mineral! Just look at the buildup of salt on a car in the snow belt in the winter...

 

[TomFOhio]

Flush it out with a bio-degradable solution.