20 Best Thermostatic Mixing Valve (2022 Updated)

I like the appearance and craftsmanship is excellent. I set the mix temperature @ 120F and the valve limits the hot water to the set temp just fine. The setting of temp is easy, just turn the knob, my previous mixing valve I had to remove the knob and make adjustments and replace the knob.

My previous valve was 1/2” and I like this 3/4” valve much better as it provides much better flow and pressures. I love the push to connect ends, it is so clean and easy.

We just had a new water heater put in, and it heats the water up so quickly, that it overheats the water to 135-140 deg. F. The water would then cool to about 105 before it would turn back on. This jump from barely hot to scalding was ridiculous, but this valve helped.

It now keeps the water a constant 120 deg. F at all the faucets. All we had to do was turn the water heater up. No more scalding water and fluctuating temperatures!.

Installed this thing fast when I was re-plumbing. I was able to turn up my hot water heater 20-25 degrees. Now I don’t worry when i’m the last to shower in my family, because I still have hot water. I did not need to adjust the Thermostatic mixing valve setting.

It was already set to a good temp. We did notice that it requires the shower to be set hotter for comfort. So I know the valve is doing it’s job.

Good Valve. Plumbing Inspector wanted to see the ASSE Cert #. They are on the valve knob, but so small you have a hard time reading them. Keep the instruction sheet and take a picture before you install the valve.

You might also want to remove the plastic knob before installing the valve so the heat from the tourch dose not melt the knob.

I use this valve to limit the hot water output from my solar hot water system. The hot water storage tank temperature sometimes reaches 160 deg F and this valve limits the water temperature leaving the valve to 125 deg.

The temperature regulation is very accurate. This is a replacement valve. The first valve only lasted 6 years but it was installed incorrectly. The valve was originally installed directly above the hot water outlet of the tank which according to Watts will cause premature failure due to thermal siphoning.

I installed this new valve 10 inches below the tank outlet per Watts installation instructions which I hope will prolong the life of the valve.

Using this to temper water from an in-boiler coil domestic water heater system. Went with this instead of the cheaper Watts units to insure fine contro, plus this has built in back flow preventers and screens.

Still tweaking my Aquastat settings, but temperature output remains rock solid. Only minor problem is that the way the screens are set in the unit, they like to fall out as you are putting the unit into the system.

This mixing valve works great. There is a bit of temperature overshoot and undershoot when you first switch it on. I need to wait a few seconds before putting my hands in the warm water. Even with the brief overshoot on temperature, the water doesn’t get hot enough to hurt.

The 3/8″ lines fit both my new 3/8″ OD hose and my existing hose from 15 years ago. The temperature was easy to adjust to 97°F (using a digital oven thermometer to provide feedback).

Installed this under residential sink with 2 handle faucet. Did not want to convert to one handle faucet, but did not want to always have to use both handles. Wanted to just turn on Hot (Warm) faucet, and not worry about getting too hot.

Now it is perfect. Hot handle can be turned on, and once it is to temp, the valve begins mixing cold in to keep temp from exceeding max. Adjustment under sink with screwdriver is easy, and seems to hold well (hasn’t needed readjustment).

This keeps from needing to lower max temp for whole house. Wanted to keep hot water at laundry sink, kitchen sink, and for shower, without installing a whole house tempering valve or reducing water heater setting (standard gas heater).

Items needed for install: Likely two extra supply lines for connecting from valve to supply stops. I ended up using supply lines and short pieces of copper tube/ferrules to complete installation.

Installed two of these to serve lavatories in public restrooms. Fast delivery. Reasonable price. Easy to install and temperature was easy to lock in. I liked the mounting holes to secure them up under the fixture.

I would like to say this mixing valve works great but I haven’t really put it to the proper test. I am using it with a 72 gallon Turbomax inverse indirect water heater that I am using to help buffer an outdoor wood boiler.

I haven’t used the wood boiler this year yet and my oil fired boiler has not heated up the Turbomax beyond 110 degrees because the system is being controlled by my radiant floor heat T stat. So the hot water after leaving the Turbomax and then the Caleffi Mixer goes through a propane on-demand hot water heater.

Crazy I know but like the product and large temp gauge.

The existing mixing valve was not adjustable and the water was never anything better than lukewarm. This valve installed quickly and allowed the temperature to be adjusted and confirmed via the temperature gauge.

I absolutelly love this valve. Smooth as silk and built to last this valve is amazing for what it is. I hope it lasts forever!

This was an exact replacement for one that was previously installed but seemed to have stopped working. The replacement was an easy install and looked like some slight improvements were made. Anyway, it works great.

No need for fancy valves in the showers or elsewhere, it works for the whole house. Also, Supply House delivered the product in record time, even during the busy holiday season.

When I first moved into my house my boiler had no mixing valve and the inspector was freaking out so I had my oil company come out and install a mixing valve. I quickly came to hate that valve which would produce only lukewarm water in the dead of winter.

So when that valve started to leak years later, I removed, but didn’t replace it. I’m perfectly happy with having super hot water, but after a few near scaldings of guests over the years I decided I’d better reinstall a mixing valve.

I went with this Honeywell model because my folks have one of these installed at their house and their hot water seems to be fine in winter. Anyway, I’ve had this installed for about three weeks now, and it seems to be doing a much better job than the valve I used to have.

It’s January in CT so the cold water is pretty darn cold, and taking showers is pleasant with the mixing valve adjusted to 120F. I’m hoping that this valve is durable and will be able to maintain the set temperature for many years.

When it does eventually need to be replaced, the union connections should make replacement a snap assuming that Honeywell doesn’t change the design/dimensions of the product.

This unit will provide stable temperature after several minutes on my 1. 5GPM shower head, but DOES NOT maintain temperature when the toilet is flushed. The temperature changes to very hot for the duration of the toilet filling process.

The mixing valve built into my shower does a better job, its just not thermostatic. I have bypassed my shower mixing valve and this unit still does the same as described above.

Works very well so far. Installed it a few months ago and have it set to prevent scalding. We used to have our hot water heater turned way down to prevent our kids from getting burned, but the problem was that we’d run out of hot water after a 5 minute shower.

We were able to put the hot water heater back to a normal setting after we put this mixing valve in and prevent the hot water tap output temperature from being too high.

This was to replace an old mixing valve. The old washers deteriorated and developed a slow leak which then started to clarify horribly. It never stopped functioning but was no longer adjustable. I found the make and model on the old ones mixing knob.

ordered from supply house and had the part replaced rather quickly.

I use this mixing vlave to lower the temperature of the water from my solar hot water storage tank to safe temperatures required for household use. It took me about 5 minutes to replace the old one and the new one is working well.

Despite a minor shipping mixup which slightly delayed the receipt of my valve from Pex Supply I have found Pex Supply to be genuinely concerned about providing excellent customer service before, during and after the sale.

When this mixing valve fails in about 10 years I will be replacing it with one from PEX Supply.

The nicest adjustable mixing valve we’ve seen. The optional thermometer makes setting water output temperature a breeze, and the overall quality of the Caleffi product is excellent!

I’ve used these valves for both domestic hot water tempering and for tempering boiler water going to radiant floor heat that is combined with fin tube zones. They perform as advertised and are easy to install and set up.

I recommend putting a temperature gauge downstream from the mixed output. I haven’t had much luck setting the mix water temperature with the liquid crystal temperature gauge that comes with the valve.

I use this mixing valve to temper the cold water line feeding an upstairs bathroom. Hot water for the shower, etc is provided by an on-demand electric water heater located in the bathroom. The problem was the cold water came directly from a well and was really, really cold, like 45-50 Fahrenheit, too cold for the on-demand water heater to handle.

Now the “cold” water is room temperature (70 F) and the system works beautifully. Thank you!.

I bought this mixing valve to replace a Chinese knockoff that a previous owner had installed on the HydroHot unit of my motorhome. The Honeywell AM-1 is what HydroHot used originally, and is much heavier duty device.

Works much better than the Chinese thing.

This is a great product that I’d easily buy it again. I purchased this to eliminate Legionella risk and increase hot water availability. To eliminate Legionella, water needs to be 140, which is dangerous at taps because it can cause severe burns quickly.

This allows me to set my water heater to 145 while keeping taps at a safe 120. The increased water heater temp has the added bonus of stretching our tank’s capacity so we don’t run out.

This is an excellent design allowing you to install it easily on either your existing or new water heater installation. We turned our heater up as high as possible (150+). This allows you to dial your output to a nearly perfect and stable temperature (we’re at 120).

With 10 people showering off one 50 gal heater, it helps significantly!.

Easy install. Good quality. Went with this because of stainless crossover pipe. Gives you ports for recirculation and cold outlets. The only issue I had was the small cold water plug started to seep after 2 weeks.

Just snugged it up and it was fine. Check the plugs in the various ports right after install.

This mixing valve is inherent in many older homes from the 1980’s through the 90’s. It’s used mostly on Oil burners with Forced Hot water and domestic hot water all in the same system, where a hot water heater is NOT used.

They tend to leak at the screw under the cap after about 5 years. If you have any minerals in your water you will see these turn a nice green color after the 5th to 10th year. The other problem with these is, they have a spring mechanism inside that under hard water conditions will fill up with sediment, usually white crystals that block the function of the valve.

Lastly the little cup at the bottom of the valve will just disintegrate over time, allowing more water to pass through the system. As well as the lower copper screw that sits at the bottom of the valve, will also disintegrate over time.

These valves tend to require being changed every 7 to 10 years, and are NOT the last line in defense to prevent scalding of children. Your shower-head is a far better method in the prevention of scalding, as these will only last for about a year in terms of good heat regulation.

I have work for a company installing boilers and used this on tank/less coil systems and it works fine when installed with proper flow restriction, When installed correctly it seems to last and work for about three to five years then the upper part needs new kit (70a).

after about 10 -15 years i find the lower main body to fail and I replace the entire unit with the same model. I believe this to be fair for the amount of water that it has handle over the years. Water condition does play another role in it life.

not to good of a life with corrosive or acidic water.

Part is outdated. This part is old and field proven. However, there are other parts for this application which are far superior. Just a swap out is fine, part configuration has not changed. But if new instal, consider taking a look on this great site for a far better alternative.

I gave it 3 stars for length of field service.

I was a bit concerned with some of the reviews, but, finally decided to go with the AM101. Very glad that I did. I downloaded the specs and installation instructions and actually, pre plumbed the installation prior to receiving the valve.

(hoping the dimensions given were correct). Upon receipt of the valve, I was delighted that indeed all was accurate. Adjustment was straight forward. I too thought I was unable to turn the adjustment handle.

I ended removing the end screw completely and figured out what the instructions meant about pulling the knob out. Works perfectly.

I needed to replace the Honeywell mixing valve on the water feed from my hot water heater and found the perfect replacement valve on build. com. The price was excellent and the order was filled promptly.

I ordered on Tuesday and it was delivered on Thursday. Fantastic! I installed it on Friday and it seems to be working perfectly. Now I can adjust the water temperature that is delivered to my faucets and shower so it is the right temperature (I like it hot).

By the way, the mixing valve enables you to store water at a relatively high temperature in the hot water tank and blends it with cold water from the cold water inlet.

Months later still works well. Replaced different brand valve, fit right in. Installed on hot water supple from oil fired boiler with tankless coil. I held back one star because not sure of durability yet.

As they say, your mileage may vary. Especially with all the different water conditions that can be encountered. I am on well water. Follow up: worked for 1yr 4mos. Due to water conditions this valve starts to stick internally with mineral buildup.

I have used 5 of these valves in past years and all last about the same time.

I had recently done a Combi boiler install and the folks loved the performance of their new unit. They were enjoying their hot showers and good supply of hot water. They had one issue come up though, there was a sink in there finished basement that was part of a daycare center and they were required to lower the hot water temp to that sink.

Not wanting to miss out on those nice hot showers we decided to toss in this mixing valve. Super Simple install with extra set of flexible supply tubes right there under the sink, no cutting or soldering any pipes, it is very easy to adjust, and it works perfectly, I monitored the output with a very sensitive fluke thermometer, held steady.

With the new lead law in effect most manufactures are clearly marking their Products on the castings and explaining the markings on their websites. This makes complying to this new law not to difficult, you just have to spend a little extra time to make sure the products meet the new code.

Honeywell however has made this exceedingly difficult with this product as they just marked the box lead Free and not the body of the valve. The body of the old valve and the body of the new valve appear identical.

I called Honeywell to inquire about the markings and how I could document that the valve that I had purchased met the new lead law. The person on the phone assured me that the valve met the new code, So I said to him, Should I just tell the local inspectors that the guy on the phone said it was ok.

Needless to say he was not amused and neither was I as he was evading the obvious. After this exchange the man’s advice was, If I am not satisfied by the product than maybe I should try another manufacturer.

This item was an intragal part of a larger installation that could not be performed until this issue was worked out, it caused unneeded costly delays. To avoid this and other issues in the future I think I will take the mans advice.

The original valve I installed about 15 years ago failed and the Domestic Hot Water from the (heating) Boiler output was about 160°F which is a setup for a very serious (skin) burn. Fortunately the same (Honeywell) valve is still available.

Replacement was simple, mounting dimensions were the same so no Piping changes were necessary. Shower is not very SAFE & comfortable!.

I’m using this valve in a closed hydronic heating system with treated water (Central Boiler’s “Inhibitor Plus” 1650XL). First valve lasted from October, 2010 to sometime during the 2013-14 heating season.

Second valve lasted until this fall (November, 2016) when I discovered the same problem – right at the mixing zone outlet area where the bronze casting meets the Teflon coating, the bronze appears to be eroded away so that hot water leaks past the seat, leaving the mix temp way too high.

Unfortunately my setup is tight and changing to a different model/manufacturer would be problematic. Great when it’s working.

This valve is a nicely machined part. I like the built in unions and check valves – makes installation a lot easier. Only time will tell if the thermostatic element will last (most of the previous brands that I have installed lasted only about 3 years.

) This model allows me to adjust it to meet the new code ( < = 120 degrees). The AM100C1070-US-1LF range 70-120 could not be set greater than about 105 degrees - and everyone complained about the "cold" water.

the directions say loosen the screw then pull on the adjustment knob and turn it to adjust water temp. should also say how far to loosen the screw. I found out it has to be loosen up almost all the way.

which is over a half inch.

I have 4 of these mixing valves running in my house in multiple applications, radiant floor water, domestic hot water, driveway de-ice, and warm water spickets. They are consistent and reliable, easy to install, and seem to last a long time (I have one yet to fail).

The integrated check valves work well. My only caution is to be VERY careful when sweating them in, the check valves melt easily. I keep a spare on hand, but it doesn’t look like I’ll ever need it (knock on wood).

Very intuitive product to set up. Fine level of adjustment. I was able to accurately set hot water temp by leaving a faucet on and turning the valve until the temp gauge was at 120 degrees. It’s much easier to do it this way than to use the valve without the temp gauge where you would be guessing and checking by running back and forth between WH and a faucet.

This also has check valves built in and mesh screen washers to protect the valve.

I have had it with this valve. I’ve had enough of irrate customers calling me back due to cold showers as a result of this valve and will never, ever use this again. It will not hold its temperature and fluctuates wildly while in use to the point of flowing nothing but cold water.

Not just one or two units. nearly every one I’ve ever installed. Even tried one in my own home and found the exact same problems as my customers, and it lived up to their complaints perfectly. I’ve always used Taco products in all my installations, but this valve is the worst I’ve ever dealt with.