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Cash Acme

Model # 24409

Internet # 203721329

Store SKU # 398764

Heatguard Tank Booster

This item has been discontinued.
The Home Depot no longer carries this specific product.

$89.97 / each



Model # 24409

Internet # 203721329

Store SKU # 398764

Store SO SKU # 732682

Heatguard Tank Booster address a hot issue with cool precision. The issue: Getting the correct mix of hot and cold water that safeguards against scalding, prevents bacteria and increases hot water system capacity. The Tank Booster solves this issue by delivering water at a safe temperature while allowing the water heater to be set at a germ-killing 140 degrees which satisfies hot water demands longer.

California residents: see  Proposition 65 information

  • Each kit includes 1-thermostatic mixing valve, 1-tee, 1-flexible hose and installation instructions
  • Protects against legionella and scalding
  • Allows water to be stored at 140°F preventing the growth of bacteria, while distributing water at a safe 120°F
  • Increases hot water capacity by up to 50%
  • Easy to install, no soldering or glue required
  • Dual listed (ASSE 1017 and 1070 approved)
  • Certified for household and commercial applications both water heater and point of use
  • Lead free DZR brass meets new legislation
  • High grade polymers, polished finish and generous water passages prevent scaling and liming (calcium and magnesium build-up)
  • Can be used with gas, electric, power vent and tankless heaters

Info & Guides

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Product Depth (in.) 
15.0 in 
Product Height (in.) 
4.7 in 
Product Width (in.) 
8.9 in 
Finish Family 
Bronze/Copper Metallic 
DZR Brass 
Product Type 
Heat Recovery Systems 
Product Weight (lb.) 
2.63 lb 
Warranty / Certifications
Manufacturer Warranty 
For warranty information on this product, please call our Internet Customer Service Center at 1-877-700-4242 


Rated 4.6 out of 5 by 27 reviewers.
Rated 4.0 out of 5.0 by Great solution to a tough problem. So your water heater doesn't seem to last long enough; guests, teenagers, large whirlpool tub. And you tried the "turn up the temperature some more". The problem is it makes it difficult to safely control the temperature at each faucet in the house, especially for guests that are unaware. You could replace your water heater with a larger unit. That's expensive. Solution: The mixing valve kit. It includes everything you need for a basic installation to most any type of tank water heater. I have a small electric heater for a single bathroom. I installed this unit and it worked as promised. The instructions, and especially the pictures are very good and very accurate. Follow them carefully. But when you disconnect and reconnect the water supply lines you will notice that the valve takes up about 6 inches of space on the hot side and 3 inches of space on the cold side. So if you do not already have new flex supply lines attached, you may need more parts and make some adjustments to reconnect the supply lines. In my case, I had recently replaced the cold supply that was an older copper flex line with a braided stainless steel supply line. It was flexible enough to handle the 3 inch difference. But on the hot side, I had to bend the 18" copper flex line a lot to make it fit back onto the mixing valve outlet. I will be replacing that supply line soon. It's best to assume you will need to replace your tank supply nipples (preferably with heat trap dielectric nipples), and your supply lines. I even replaced my shutoff valve from a gate valve to a ball valve. Once that was done, I flushed my tank, flushed my lines, and adjusted the temperature. The valve is set for 120 degrees, but I wanted 130. So I set that at 130. I am not sure it will adjust above 130 degrees. I then set my tank at 150 degrees, and left the allen wrench in the valve for future adjustments if needed. One thing I would do differently: I would set my tank to my new temperature (150 degrees) before installation and verify temperature with a temperature probe because water heater dials are not very accurate, and you cannot check the internal temperature once the valve is installed. I decided to clean the strainers to be sure they were clean from the flush. It's important that you depressurize the valve by turning the cold supply off and opening a hot faucet to relieve pressure. I did not open a hot faucet and when I removed the cold supply hose from the mixing valve, the check valve popped out of the valve body. While tech support was easy and fast to reach, I had to figure out how to reassemble the parts myself. (yes it works again.) I'm glad I checked because the screen had debris in it. The thermo-strip was installed but will be useless as I will be insulating the pipes. And it appears only Home Depot will warrant this unit as the manufacturer requires licensed plumber installation only. If your water heater is old, you're better off replacing it with a larger unit. But if you have a newer tank water heater in good condition then you can use this tank booster mixing valve kit to increase your hot water supply. Just be ready to buy new supply lines. February 8, 2015
Rated 5.0 out of 5.0 by Plenty of Hot Water and Peace of Mind I just installed the HeatGuard Tank Booster, and I am very pleased with the results, though it did not “boost” my water heater’s output because the temperature was already set to 150 degrees. Our water heater had been unable to meet our needs during peak usage times before we increased the temperature. The downside was that the hot water was scalding when not mixed with cold water at the tap. We had never been concerned about burns in the past, but now have a newborn and don’t want to risk injury to him. The HeatGuard enables us to safely keep the water heater temperature very high so that less hot water is needed, mixing cold water in the supply line rather than at each faucet. The major benefits are that the hot water at each tap is no longer a scalding risk, and less hot water is used by appliances that simply draw unmixed hot water such as the washing machine and dishwasher. The parts and components are all of excellent quality and the manufacturer has a great installation video on their website using another of their products, Sharkbite water heater connectors. However the instructions and video were not very helpful for my installation--they seemed simple enough, but I ran into several complications. First, the water lines are cemented to the nipples on the top of my water heater. Second, my gas water heater has an expansion tank mounted on the cold water supply line that is only supported by the copper pipes. Because of these issues, the manufacturer's recommended push-fit flexible connectors were not an option. Instead, I used some of their other push-fit adapters to connect to each end of both the hot and cold water lines. Even if you do not have these particular difficulties with your water heater, it is likely that additional components will be needed to complete the installation unless your water heater is already connected with flexible lines on both the hot and cold side. This is somewhat disappointing considering the price of the kit, but makes sense because every installation is somewhat unique. I recommend a test assembly before cutting the water lines to ensure you have all the right connectors and fittings and know where they go. Also, be aware that both ends of the included flex pipe have rubber seals, but all other connections will require Teflon tape, which is not included. See the attached photo for my completed installation using the referenced push-fit connectors. For this method of installation, remove a 1” section of the cold water supply line (leaving 2” clearance on one side and 1” on the other), and 7.5” from the hot water supply line (leaving 1” clearance on both sides). I found that it was easier to install on the cold water line using a slip-fit connector with built-in fittings on either end rather than to add adapters to both sides of the T piece included in the kit. The end result is a very solid connection on each water line that is able to support the weight of the pressure relief tank. I went ahead and turned the valve temperature adjustment, which comes set at 120 degrees, to the highest setting of 130 degrees. This provides hot water that is 118 degrees at the faucets closest to the water heater. I am comfortable that the burn risk is minimal at that temperature, yet the water is still hot enough to clean with, warm up a bath or take a hot shower. While installation took around an hour and cost a bit more than expected, the peace of mind knowing that there is no longer 140+ degree water flowing to the taps in my house is well worth the price. July 24, 2013
Rated 5.0 out of 5.0 by Great Product, Increases Usable Hot Water The TankBooster is an extremly easy to install, average DIYer project that can be done in 15 minutes. After installing the Tankbooster I have noticed a significant increase in usable hot water. The project is simple, turn the water off to the tank and run a faucet to drain the lines. Turn the water heater off remove existing connections and put tee on cold water inlet, Mixing valve on hot water outlet and thread the supplied flex hose from Tee to Mixing valve. Then simply thread back on water heater connectors, I changed my lines out using Sharkbite Water Heater connections and then added a Sharkbite temperature gauge that inserts into a Sharkbite Tee, not necessary to complete the install but I wanted to upgrade the flex hoses and add in a temperature gauge to monitor. Once complete turn water back on, turn Hot Water Heater back on and crank temperature to 140-150 degrees. The mixing valve regulates the temperature down to 120 degrees by mixing in cold water so your tank uses less hot water to reach the same desired 120 degree outlet temperature thereby increasing the usable hot water you can get out of the same tank. Tankbooster prevents scalding by regulating output temperature. By raising the temperature in the tank you prevent legionella bacteria from growing because it cannot survive in temperatures that high. Awesome product and a great way to get more hot water out of your existing tank. May 20, 2014
Rated 5.0 out of 5.0 by Heatguard tank booster money saver The tank booster has saved me money already and I installed it about a month ago. I followed the directions which were very east to understand and got a little excited and ended putting the cold water fitting on upside down. I cant believe I did that Dummy. After looking at the arrow and re-reading the directions I put the fitting on correctly. Set the water at the required temperature of 120 degrees I thought I restarted the hot water heater and after several hours we still had no hot water. Went back to hot water heater and realized that I did not turn the control knob from pilot to run, re-started the Hot Water Tank we had hot water in about 35 minutes. A total of 4 adults taking showers or baths daily and every other day, Dishwasher every evening, Washer running on Friday and Saturday one child taking a bath every other night. I have noticed my gas bill has started to drop and the water consumption has started to drop. Be sure to shut off the cold water coming to the tank, follow the directions, and take your time. As we go forward I will continue to monitor the amount of water used and the gas consumption. I expect to recover the initial investment in less than a years time. Great idea and a sure fired money saver. . January 24, 2014
Rated 5.0 out of 5.0 by Product works great Much easier to install than either Honeywell or Califi mixing valves! May 12, 2015
Rated 5.0 out of 5.0 by FANTASTIC!!!!!!! I could not be happier with my purchase. The tank booster was an absolute breeze to install(I used a sharkbite water heater hose and ball valve for an even simpler installation). It took me approximately 15 minutes from start to finish. I have a 40 gallon water heater that the wife and kids were running empty every morning. Since installing the tank booster they can all shower back to back and I still have a long hot shower waiting for me when they are done. Much cheaper, faster, and easier than buying a larger water heater. January 3, 2013
Rated 5.0 out of 5.0 by Wow! It works great The Heatguard Tank Booster is the answer to getting the the right mixture of hot and cold water that avoids scalding and still prevents bacterial growth in too cool water. Even more, it really does increase hot water system capacity. We have 3 baths in our home with 4 women taking daily showers and or baths. Our walk in tub holds over 50 gallons of water and we never run out anymore after installing this genius invention. Two of our home's occupants are handicapped and have trouble controlling water temperature, but no more. I would highly recommend the booster in homes where scalding may be a problem (that one thing alone makes it worth the reasonable price). The kit includes a thermostatic mixing valve, a tee, a flexible hose and installation instructions that make it a DIY project dream. Of course if you don't do plumbing it should not cost you much to have it plumbed in since it is such a simple design. We have natural gas for our water heater and it has cut down on the amount of gas we use. I would imagine that folks with electric water heat will se a dramatic cut in power bills too. January 27, 2015
Rated 5.0 out of 5.0 by Good temperature regulation I tried the Cash-Acme Heatguard Tank Booster with my tankless gas water heater. With my low flow, the tankless on-demand heater alone tends to scalding temperatures. The Heatguard is a thermo-valve in the hot output and a cross-connection to the cold supply. If the hot water is too hot, it bleeds a little cold water in to temper it. The included fittings are complete for a standard tank heater with 3/4" stubs. If it is plumbed with 3/4" flex to the house, or have PEX with some slack, this goes right in. With rigid plumbing, or with a tankless heater, you will probably need another fitting or two. In preliminary testing it works fine. Instead of a smaller flow of too-hot water, I get a slightly larger flow of just-hot water. In my house, the stock setting gave 110 degrees at the kitchen tap. It can be adjusted higher, they say to trim for 120 degrees. However I find 110 deg to be an excellent limit for hand washing. Time will tell if I need to trim up for optimum bathtub and dishwasher operation. (Most modern dishwashers will hot-up lukewarm water.) The parts appear to be very excellent quality. The fittings are good brass. Water passages are very ample for any house. However the "T" fitting should have a proper hex for good wrench grip, not two tiny flats. (All the other fittings are nicely hexed.) And the packaging is very annoying. It is heatseal bubble pack to keep it all together in the store. But cutting around the plastic was a real chore with good scissors. Then some little bits fell out, but all the big bits are in individual pockets with cardboard glued to the plastic. I started knifing the cardboard but there was danger of stabbing the hose or other parts. As you see in the picture, I made a real mess getting the parts out from under the cardboard without damage or losing any parts. This product should be in a box like a large flush-valve. February 9, 2014
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