Question about Rinnai Water Heaters

3 Answers

My rinnai has build up in the heat exchanger

The code that shows on the control is LC. what can I do?
Is there a chemical that I can flush through it?

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  • you have a lime controll issue , you need to flush the unit using food grade vinegar. go to the rinnai web site for instructions. it is a pretty simple solution they make a kit to flush your unit if it was installed with an isolation kit.

Posted on Jan 10, 2009

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Whiterussian is speaking without product knowledge. The first answer is correct, to follow the manufacturers instructions and flush with vinegar.

One of the most basic and simple things "professionals" miss is to always read and follow the instructions. They probably won't ask for directions when they're lost either.

Posted on May 05, 2009

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Not really, commercial boilers are cleaned with concentrated surfuric acid which takes a trained professional with knowledge in organic chemistry to control that kind of dangerous reaction. CLR might remove some of the calcium deposits; but I have never tried using it. I usually buy a new heat exchanger and recycle the old one. Unfortunately without a water softener supplying the tankless it will just happen again; that's why in the fine print of your warranty it is void if you don't have a water softening system installed.

Posted on Nov 28, 2008

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Sorry to read about your problem, I hope this helps you out.
The 130 is your temp setting

Scale Build-up in Heat Exchanger (when checking maintenance code history, "00" is substituted for "LC")
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The display will alternate between the LC code and the temperature setting.

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I tried to help you. Please help me and Rate/Vote on my response. We take the time to answer your question. take the time to rate us.Thanks and good luck

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