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Clean indirect using tankless descaler?

sunlight33 Member Posts: 247
edited February 24 in THE MAIN WALL
I have a 50-gal indirect water tank, can I use descaler made for tankless water heater to clean the inside? Basically I will drain the tank to half full (since the heating coil is in the bottom half of the tank), pour the descaler in and let it sit for an hour or two. What do you think?
Edit: Or I can dump a 2-pound bag of citric acid into the tank, is that going to achieve the same result?


  • Big Ed_4
    Big Ed_4 Member Posts: 1,654
    What make indirect ? What is the issue ?
    I have enough experience to know , that I dont know it all
  • sunlight33
    sunlight33 Member Posts: 247
    Just want to clean heating coil inside to make better heat transfer, tank is Viessmann.
  • heathead
    heathead Member Posts: 140
    Does the tank have a port clean out. What is the tank made of. If you have a port, open it up and pressure wash the inside and read the Viessmann directions for cleaning. If it is a stainless steel tank do not use any metal brushes, plastic only. Pulling the port will let you see what is going on inside and how much build up. Not much room to work but gives some idea of build up, What model tank do you have? Have you looked for directions for cleaning from Viessmann's web site.
  • sunlight33
    sunlight33 Member Posts: 247
    edited February 24
    Viessmann recommended pressure wash and chemical cleaner (no muriatic acid) . Mine doesn't have the port (only 79-gal and above units have them) so can I do it only using citric acid?
  • sunlight33
    sunlight33 Member Posts: 247
    My original question was for product like this one:
  • bucksnort
    bucksnort Member Posts: 80
    I would think that you just can't dump a descaler in a tank and expect it to work effectively. Wouldn't it be better if you circulated the cleaning solution around the coils? Kinda on the lines of a pump setup to clean a mod/con?
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