OT - descaling a tankless hot water heater

[Harrydawg]

Someone recently told me that our tankless hot water heater needed descaled every year or so. Has anyone had any experience doing that - or did you have a plumber do it? Thanks

[SteelCurtain74]

I did it back in January on our two. Do you have a Rinnai or another brand? It wasn't hard to do and saved me a good bit of money. Watched a couple of videos on YouTube and went to town. Plumber quoted me around $500 - $600 to do it. I did it for less than $100.

[Harrydawg]

Norwitz - good information and thanks I was just watching a video

[BiscuitEater]

Someone recently told me that our tankless hot water heater needed descaled every year or so. Has anyone had any experience doing that - or did you have a plumber do it? Thanks

Did ir 'every' September for the last 15 years and we sold the house in May. Our Rannai unit was it the attic so you want to pick a cooler day. There were excellent instructions.

Basically, go to Costco and get two big jugs of white vinegar, empty in a 5 gallon bucket, use a small submersible electric pump in vinegar, isolate unit from fresh water so that you can pump the vinegar through the unit for 45+ minutes, then open the valve of fresh water to run through the unit but capture outflow in another bucket. Remove the hoses for the vinegar and run fresh water through the unit by cutting on a couple of hot water faucets. Clean up.

It's not complicated; just follow the diagram when connecting hoses! Every manufacturer should have a diagram and instructions! You will know if it does a good job if the vinegar turns blue!

This IS the secret to long-lasting tankless systems

[Dawgology]

We got ours three years ago and I?ve never done this. Perhaps I should look into it.

[Extendedcab]

Did ir 'every' September for the last 15 years and we sold the house in May. Our Rannai unit was it the attic so you want to pick a cooler day. There were excellent instructions.

Basically, go to Costco and get two big jugs of white vinegar, empty in a 5 gallon bucket, use a small submersible electric pump in vinegar, isolate unit from fresh water so that you can pump the vinegar through the unit for 45+ minutes, then open the valve of fresh water to run through the unit but capture outflow in another bucket. Remove the hoses for the vinegar and run fresh water through the unit by cutting on a couple of hot water faucets. Clean up.

It's not complicated; just follow the diagram when connecting hoses! Every manufacturer should have a diagram and instructions! You will know if it does a good job if the vinegar turns blue!

This IS the secret to long-lasting tankless systems


THIS! This is the advise my house inspector gave me 2 years ago when I bought a house with a tankless water heater.