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Rectorseal

RectorSeal Calci-Free 68708 Tankless Water Heater Cleaner, Easy Application, Plumbing, 1.2 lb

  • Based on 671 reviews
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Features

  • APPLICATION: Calci-Free is an efficient chemical descaler specifically formulated for tankless water heaters found in residential and commercial applications
  • EASY APPLICATION: Tankless water heater cleaner is easy to use with no strong odor; can easily be applied to any type of tankless water heater; no splash crystal product
  • CONVENIENT: Fast acting and cleans heat exchanger quickly; more effective than vinegar; restores water flow, pressure, and circulation in twenty minutes
  • SPECIFICATIONS: Calci-Free tankless water heater flush; 1.2 lbs; contains a unique combination of organic and inorganic cleaners and patented corrosion inhibitors; for routine cleaning to remove calcium and other solid deposits from heating coils in tankless water heaters
  • FOR THE TRADESMAN: RectorSeal is recognized as a leading provider of quality solutions for the professional trades serving heating, ventilation, and air conditioning (HVAC/R), plumbing, electrical, and construction markets

Description

Calci-Free is an efficient chemical descaler specifically formulated for tankless water heaters found in residential and commercial applications. Tankless water heater cleaner is easy to use with no strong odor. Can easily be applied to any type of tankless water heater. No splash crystal product. Fast acting and cleans heat exchanger quickly. More effective than vinegar; restores water flow, pressure, and circulation in twenty minutes. Calci-Free tankless water heater flush; 1.2 lbs. Contains a unique combination of organic and inorganic cleaners and patented corrosion inhibitors. For routine cleaning to remove calcium and other solid deposits from heating coils in tankless water heaters. FOR THE TRADESMAN: RectorSeal is recognized as a leading provider of quality solutions for the professional trades serving heating, ventilation, and air conditioning (HVAC/R), plumbing, electrical, and construction markets. From the Manufacturer Calci-Free Tankless Water Heater Flush Cleans heater coils thoroughly. Restores pressure and circulation in minutes, with no strong odor. Calci-Free is a unique, economical, biodegradable cleaner containing a combination of organic, inorganic and corrosion inhibiting ingredients. It is easy to use and works twice as fast as other cleaners.-1.2-Pound (12-Piece)

Specs & Other Info

SpecificationDetails
ManufacturerThe Rectorseal Corporation
BrandRectorseal
ColorWhite
Part Number68708
Weight1 pound
Dimensions2.5 x 2.5 x 6.25 inches
OriginUSA
Model Number68708
Package Quantity1
Included ComponentsCalci-Free
Batteries RequiredNo
Release DateJune 12, 2012

Frequently asked questions

The Rectorseal Calci-Free Flush is primarily used for cleaning tankless water heaters. It helps in removing calcium build-up which can affect the performance of your heater.

The frequency of use depends on your water's hardness and the manufacturer's guidance. However, on average, it is recommended to use it once a year to maintain the efficiency of your tankless water heater.

Yes, it is. The product makes it quick and simple to clean your tankless water heater. It is designed to be user-friendly with instructions provided on the packaging.

While the Rectorseal Calci-Free Flush is compatible with most brands, it's always best to check with your water heater's manufacturer to ensure the product's suitability.

Similar Products

Top Amazon Reviews

🚀 Abunda's Overview

This is our summary and key points to consider based on customer reviews.

The Rectorseal tankless water heater cleaner receives overwhelmingly positive reviews from customers. Users find it significantly more effective than alternative cleaners, such as vinegar and Flow Aide, reporting that their water heaters operate at peak efficiency after use. Notably, reviewers with both gas and electric tankless heaters shared high praise for its performance, demonstrating that the product works great in different settings.

Pros

  • 🚀 Efficiently cleans and flushes tankless water heaters, improving their operation.
  • 🎉 More effective than vinegar and Flow Aide, as reported by users.
  • 💥 Capable of removing large amounts of scale and grit from heaters.
  • 💡 Can be applied in both residential and commercial settings, compatible with both gas and electric heaters.

Cons

  • 🥴 Each container of the product is primarily intended for single use, which may not be cost-effective for some users.
  • 😓 Some users mentioned that there were still residues in the water heater post-cleaning, necessitating a thorough flush.

Should I Buy It?

If you own a tankless water heater and are looking for a product that can improve its efficiency by effectively removing build-up, then the Rectorseal cleaner is a sound investment. However, if you were hoping to get multiple uses out of a single bottle, you might want to consider other options. Just keep in mind to thoroughly flush the heater after cleaning to get rid of any residue.

    • Works better than Flow Aide in my opinion
Background you can skip: We have run our Tankless Noritz N0751 since 2008. We initially had the plumber come by yearly to do a flush at an outrageous cost and they used vinegar. 6 years in the unit would not kick in a fast, water flow was down and sometimes wouldnt even kick in. Plumber diagnosis: we have hard water and these units simply wont last long in that environment. Buy a new one for 3000$ for a retro fit install. I booted them out. Installed - should have done it years ago- isolation valves and used flow aide based on online recommendations. Ran diluted flow aide for one hour and came down to find the flush water black. The machine ran like new. Conclusion: Flow Aide > Vinegar, i.e. Flow Aide is better at cleaning than vinegar. However, flow Aide has gotten expensive. Recently I cleaned with the last bit of Flow Aide and when it ran clean I decided to try RectorSeal right after to see if it would still help. Whaddaya know, after 45 minutes i came down to find the water BLACK again. So my view is: RectorSeal > Flow Aide > Vinegar. Pros: Cleans well in well water / hard water environment. Our Nortiz Tankless is turning 15 with no end in sight. Beats the alternatives in effectiveness ... and in price Cons: None yet. ... show more
Reviewed in the United States on December 19, 2022 by Rick V
    • Works!
Really works. Effective.
Reviewed in the United States on October 25, 2025 by drband
    • let this potion do the work for you.
Let me tell you about this magical little potion called the Rectorseal Calci-Free Tankless Water Heater Flush. First off, the name is a mouthful – it's like they couldn't decide whether to call it a flush, a descaler, or a fancy spa treatment for your water heater. When you open the tub, it looks like a batch of those fizzy bath bombs that are all the rage these days. But instead of turning your tub into a lavender-scented oasis, this stuff is going to give your tankless water heater the deep cleaning it deserves. And let's be real, those things probably need it after all the hot water abuse we put them through. The instructions are simple enough: dump it in, let it do its magic, and boom – your water heater is as good as new. No more weird buildup or funky smells when you turn on the shower. Just pure, unadulterated hot water goodness. Now, I know what you're thinking: "But wait, couldn't I just use some good old-fashioned vinegar for this?" Sure, you could. But where's the fun in that? The Rectorseal Calci-Free is like the spa day your water heater never knew it needed. It's like a deep tissue massage for all those hard-to-reach places. And let's not forget the best part: you don't even have to get your hands dirty. Just toss it in and let the little fizzy guys go to town. It's like having a tiny cleaning crew working tirelessly inside your water heater. So, if you're tired of dealing with mineral buildup and want to give your tankless water heater the royal treatment, do yourself a favor and grab some Rectorseal Calci-Free. ... show more
Reviewed in the United States on March 24, 2024 by Scottie
    • Worked on my water heater flush, but pricey and makes noxious vapors
I did a flush on my propane on-demand water heater for the first time after 4 years of use. When I added this to the mix water in a 5 gal bucket, it off-gassed with a nasty smelling gas that I was not expecting, and I almost took a big whiff of it before I realized what was happening and turned my head away. There should have been a warning about that...be very careful of the vapors when initially pouring it into the water. The crystals then fell to the bottom, it has to be mixed in physically to dissolve all the crystals. Because it creates an acid solution, use a plastic bucket and plastic or wood to mix, do not use metal. I then ran this through my WH for 20 minutes as instructed. It went in clear and after 20 minutes I had an orangey-pink solution with some orange particles in the bucket. I used rubber washer hoses with brass hose ends. The 2 hose ends that were submerged in the bucket corroded during use, turned from a shiny brass gold to a dull grey color. I would consider the WH flush project a success, judging by how much scale ended up in the acid solution. Also, be careful how you dispose of the waste solution - it is a pretty strong acid so it will eat through metal, stone and concrete. I looked it up after the fact (should have done this before) and discovered it is just "sulfamic acid" crystals under a fancy trade name and in a fancy container. You can buy the same sulfamic acid off the shelf at a store for 1/3 the price, which is what I will do next time. Poor value for the money when you consider alternatives are readily available, but it was effective for flushing my WH. ... show more
Reviewed in the United States on April 19, 2023 by David N. Hollas
    • Easy, affordable, and does what it says
Mix 2 gallons of water with it in a 2 gallon bucket and circulate it in your water heater following the instructions. It says to use for 20 minutes, but it'd been a while since I kept up with the routine maintenance so I ran it for 2 hours. You should've seen the water after. Definitely cleaned a lot from the tank. I'd hate to see what the pipes in my wall accumulate ... show more
Reviewed in the United States on June 17, 2025 by Rando
    • Perfect for DIYers
I used this to perform a flush on my tankless heater. Much easier than vinegar.
Reviewed in the United States on November 4, 2025 by David Y.

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