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Rectorseal

Rectorseal 68708 1.2-Pound Calci-Free Tankless Water Heater Flush

  • Based on 650 reviews
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Arrives Friday, Sep 12
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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.

    • 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
    • Did the trick
Worked great. Cleaned my heater. Would buy again. It's cleaner for a tankless water heater. What more can I say? It didn't sing songs or dance but it DID descale my heater.
Reviewed in the United States on March 29, 2025 by BrianD
    • Water softner
Perfect as described.
Reviewed in the United States on July 20, 2025 by Christine
    • 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
    • Seems to have worked well
Review Image by Robert's reviews Robert's reviews
Review Image by Robert's reviews Robert's reviews
I was unaware that on demand water heaters needed to be flushed out from time to time, until my first one died (after a dozen years or so) and the service guy said "When was the last time you flushed this one out?" He seemed surprised that it lasted 12 years with no maintenance. They are not inexpensive to replace, so decided a bit of an investment in maintenance might prolong its life. And with products such as this, it is easy to do. You can get a kit, or make your own. A sump pump, two longish washing machine hoses, and a bucket. When yours was installed it should have two hose connectors on the bottom. Close off the water in and out, take off the caps, attach the hoses, turn on those valves to the heater from the bypass (sump pump out goes to cold in, and the hose back to the bucket is hot out, but probably does not matter if you do it backwards). This product you mix with a gallon of water in the bucket. I understand that vinegar does the same thing, but I really dislike the smell of vinegar, so thought I would give this a try. When cleaning, this product, mixed with water, gets pumped up through the hot water heater, and comes out the other side, back into the bucket. I read to let it run for about half an hour, which I did. It started as a cloudy solution, and after half an hour was a clear fluid, with a slight bluish tint. I did not notice any odor at all. When I did open the container of this powder, there were some big clumps, so did have to break it up with a screwdriver to get it out of the container, but not a big deal. Once I added water it quickly all dissolved. Once I was done, I let the cold water run through and out into the bucket, took about 2-3 gallons until that water was clear, then closed back up everything, and put all valves back where I had found them. This morning had a nice hot shower, so seems to be working fine. It is hard to say "This worked" because it is preventing a potential future problem. There was some "gunk" around the rim of my bucket when I was done, so although I didn't see anything in the water, it hopefully dissolved some scale and other stuff as it cleaned inside. I guess the only way for me to confirm it working is to do this every year, and see if the water heater lasts longer than my last and when it does to see how much buildup it has. It might lower by gas use slightly (easier to heat water), but on demand water heaters use so little gas anyway, would be impossible for me to see any significant change and attribute it to this cleaning. But it was easy to use, probably did what it was designed to do, and didn't have an odor. Hopefully it will extend the life of our unit. ... show more
Reviewed in the United States on May 24, 2023 by Robert's reviews Robert's reviews
    • 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

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