How Much Vinegar Do I Need To Flush A Tankless Water Heater?

Beginner Info, Tankless Water Heater

how much vinegar do I need for a tankless water heater
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So, how much vinegar do I need to flush a tankless water heater?

Well, in this post, I would be walking you through the nuts and bolts of the best practices to flush your tankless water heater with the help of vinegar.

To be honest, I’ve been in the smart home domain for quite some time now, and I can strongly affirm that STILL, the end-users aren’t well informed about the various aspects of a tankless water heater.

Anyways, in this post, I would be discussing anything and everything that I could relate to vinegar and its uses in an indoor tankless water heater.

Does it make sense?

So, without any further ado, let’s begin…

Without wasting any time, let’s get straight to the answer to the query, how much vinegar do I need to flush a tankless water heater?

Well, you would be needing 3 to 4 gallons of vinegar to flush a tankless water heater that is used for small to mid-sized homes.

Moving further, we would also explain to you the best way to flush your tankless water heater with vinegar.

So, stay tuned…

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By following the below-mentioned steps, you would be able to reap maximum benefits when it comes to using vinegar for flushing your tankless water heater.

But, before we dive deep into the steps, I would request you to be ready with the below-mentioned things so that you can easily expedite the process without any hassle.

  • A five gallon bucket
  • Three to four gallons of distilled, food grade white vinegar
  • Two 3/4 inch connection drain hoses
  • A submersible pump

Steps To Be Followed:

  • Turn the gas valve OFF and keep the unit ON
  • Both hot and cold valves need to be turned off and also, you need to remove the drain caps on both the valves
  • In the next step, you need to place the five-gallon bucket underneath the hot water side, and also, you need to carefully turn the red drain valve to the “ON” position and use the bucket to drain the unit of excess water still inside
  • The aforementioned step needs to be repeated on the cold water side as well
  • Once you’re done with all the aforementioned steps, the next thing that needs to be done is to connect a hose to the submersible pump and place the pump with the connected hose into the five-gallon bucket
  • At the same time, you need to make sure that the power cord stays out of the bucket
  • Now, its time to connect the pump outlet hose to the cold water drain valve
  • Also, connect a drain hose to the hot water drain valve and place the end of the drain hose into the bucket
  • Here comes the most important step – pour carefully 3 or 4 gallons of vinegar into the bucket in such a way that pump is completely submerged. Then, open both drain valve lever handles on the isolation valves and turn on the pump for at least an hour or so…
  • In order to maximize benefits, you’ll have to change the vinegar solution after 30 minutes and repeat
  • Though the unit will try to fire up but it couldn’t as the gas being OFF
  • As a result, you’ll notice an error code 11, you don’t have to RESET the unit, keep it in mind
  • You need to turn the pump off and close the cold water drain valve after atleast an hour. Remove the hose from the cold water drain valve and replace the cap onto the drain valve outlet
  • Drain the liquid only after removing the pump and drain hose from the bucket
  • Once the bucket is empty, place the hot water drain hose back into it and open the cold water main valve
  • By doing so, it would be quite easy for you to flush out the heater with fresh cold water
  • Flush atleast for 5 minutes
  • In the case of the condensing unit, you need to place a bucket beneath the unit and twist open the drain point located directly under the water heater in order to drain out any descaling medium that might have got accumulated in the unit
  • Now, it’s time to turn the main inlet valve to the “OFF” position
  • For additional maintenance, what you need to do is to unscrew and remove the water filter for cleaning
  • It is quite possible that some water may flow out
  • Remove any debris if present by cleaning the filter under running water
  • Place the dry filter back into the port and make sure it is tightly fitted to avoid any last minute misadventure
  • Now, turn the drain valve to the “OFF” position. Then, unscrew and remove the drain hose
  • Replace the drain cap and make sure it is tightly screwed
  • Once you’ve expedited all the aforementioned steps carefully, then you’re almost done
  • Now, its time to turn both the hot and cold valve back to “ON” position and turn the gas supply back on
  • If you’ve got an error code 11 then now its time to reset the unit by powering it OFF first, and then powering it ON

For more information related to descaling, you can check this link.

Wrapping Up

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