Tankless Water Heater Cleaning Solution?

[Cindy Grapperhaus]

We have always payed the company who installed our tankless to flush it out. We just flushed it for the first time ourselves using vinegar. When we went to use the kitchen faucet it was clogged. Our handyman thinks that maybe we should have used something stronger than vinegar like CLR. He said vinegar only breaks up the deposits but does not dissolve them and that is why they got trapped and caused a clog. Is CLR safe to use and do you think that will keep a clog from occurring the next time we flush it out?

 

[Reach4]

We have always payed the company who installed our tankless to flush it out. We just flushed it for the first time ourselves using vinegar. When we went to use the kitchen faucet it was clogged. Our handyman thinks that maybe we should have used something stronger than vinegar like CLR. He said vinegar only breaks up the deposits but does not dissolve them and that is why they got trapped and caused a clog. Is CLR safe to use and do you think that will keep a clog from occurring the next time we flush it out?

As long as you flush it out, CLR should be fine. I would go with a phosphoric acid based cleaner. For the clog possibility, I suggest that you screen the recirculated liquid.

http://www.speedclean.com/news/tankless-water-heater-maintenance/
http://www.speedclean.com/wp-content/uploads/2015/06/SpeedyBright-SDS-0315.pdf

I would probably dilute phosphoric acid down to maybe the 15% level. That would be stronger than vinegar.

 

[Sponsor]

 

[Cindy Grapperhaus]

As long as you flush it out, CLR should be fine. I would go with a phosphoric acid based cleaner. For the clog possibility, I suggest that you screen the recirculated liquid.

http://www.speedclean.com/news/tankless-water-heater-maintenance/
http://www.speedclean.com/wp-content/uploads/2015/06/SpeedyBright-SDS-0315.pdf

I would probably dilute phosphoric acid down to maybe the 15% level. That would be stronger than vinegar.

Thank you. How do you dilute it down to 15%? And how do you screen the recirculated liquid? I am hoping that if we flush it more regularly that maybe we will only need vinegar.

 

[Reach4]

Thank you. How do you dilute it down to 15%?

Start with 30% and add equal amounts of water. Or maybe start with something higher, and add more water. Actually I don't know the actual concentration, but ResCare is roughly that I think. There is another source that may be less approved for use around plumbing that I used when I cleaned out my tank water heater.

And how do you screen the recirculated liquid?

Maybe tie an old sock or two over the recirculation hose in the bucket.

Yes, vinegar is easy to find and already too weak to dilute.

 

[jbiddle]

If the system was closed off to the house when flushing, and the unit was rinsed afterward while still being closed off to the house, how would anything get to the house? If it did, wouldn't CLR or any other chemicals also have that same ability to get into your house water? I think that's why they spec out food grade vinegar for flushing

 

[cargosdad]

We have always payed the company who installed our tankless to flush it out. We just flushed it for the first time ourselves using vinegar. When we went to use the kitchen faucet it was clogged. Our handyman thinks that maybe we should have used something stronger than vinegar like CLR. He said vinegar only breaks up the deposits but does not dissolve them and that is why they got trapped and caused a clog. Is CLR safe to use and do you think that will keep a clog from occurring the next time we flush it out?

Do you have Isolation valves for flushing your unit?

 

[Tony Welsh]

Step 1 is to determine the quality of water in the home so you can identify the correct method or chemical. If your on city water , a simple flush should suffice, perhaps a hydostatic flush but a check of the pressure rating would have to be taken and followed.

If your on a private system- "treated or not" an analysis should surly be done. Nova Scotia and many parts of Canada have naturally high mineral deposits. The water heater may need annual or even monthly treatment. I would not use this type of product without first having a water quality test performed. There are locations that have such poor / corrosive water quality- tanks are replaced every 18 to 24 months. These are not ideal locations to use this type of appliance.

The products heat exchanger is very relevant. These are the core components of most tank less water heaters. Stainless steel is very durable while aluminum is subject to design issues and certain chemicals. PH levels are very important.
You are best advised to read the maintainiance portion of the product and follow.

 

[makeluck]

I use this currently to keep the scale off the internals.

https://www.amazon.com/gp/product/B...KETXQ&linkId=e53c94899e7b2fb194a8af983504fedc

 

[Nakopf]

I avoid anything that isn't food-grade. Sure, CLR would work - and well... but look at the MSDS - it's nasty stuff.

Vinegar is food-grade, albeit it's a little weak as a de-scaling solution.

I use a citric acid solution (I noticed it was the active ingredient in a few commercial tankless flushing products). It's food safe, safe to handle, relatively strong, stores well (it's a powder), mixes readily, and is super cheap.