I've been reading customer reviews on Amazon on the Watts pump, and ran into a potential issue related to heat traps on the outlet pipes on the top of the water heater that . Results as noted in reviews are mixed...some say the heat traps weren't a big issues, others more concerned.
Any experts care to opine? My water heater (Bradford White M-4-5036FBN) does appear to have the heat trap in place. Sounds like I could remove the heat traps, or have the plumber remove it since he'll be there doing other work.


Customer reviews discussing
Summary
Remove the heat traps if you have them
By Steve on September 2, 2019…I needed to remove the two heat traps in the 3inch nipples coming out of the hot water heater.
2).… see moreWorks on my water heater that has a "heat trap"
By rykauff on December 28, 2019…I hesitated buying this pump based on other reviews I read that mentioned an incompatibility with a water heater that is designed with a "heat trap".,I called my water heater manufacturer - AO Smith and they confirmed it has a heat trap.… see moreWorks great even with heat traps installed
By K on January 17, 2021I had one of these before but had left it unplugged too long it locked up. Since the new home automation has gotten so cheap and easy to use I bought one again. Just installed it today working great my RUDD heat pump water heater has the heat traps installed not having any problems with getting hot water. I bought GE C automation smart plug, and motion sensor. They can be configured from any smart phone the motion sensor is tiny 2"x1" with magnetic mount stick it to any metal. The motion turns on the pump when it sees motion in my kitchen area runs for 10 minutes then delays 30 seconds before allowing to turn on again if it still sees motion. I read about the issue with the heat traps this pump should not have any problems with heat traps your moving the water in direction which opens the traps allows it to work. What I suspect some are seeing is that they have very long run to the spot where the cross over is installed under the sink. The Watts book says to put connect two cross over valves in those cases so you get more flow though that is what I did because I only had warm water at first. see lessDont buy if you have a heat trap on your water heater IE all new water heaters
By Little Big Kat on February 5, 2020I installed this pump and valve as instructed and subsequently tested the system. I was never able to get any hot water just luke warm throughout the house. Called customer service and they said it is a known issue with water heaters with a heat trap. I believe most modern water heaters have a heat trap. So beware this is not compatible with all tank water heats like advertised. see lessWorks Pretty Well With Remote Control, Even With Heat Trap Nipples Left In Place
By B. Aller on January 8, 2019I installed this hot water recirculating pump, and use it with the Etekcity remotely controlled outlet also sold on Amazon, as it is much more efficient to run the recirc pump only when needed. If not, run it with the timer, as running it continually is hugely inefficient). I had float-type heat trap nipples (on a Rheem hot water heater bought in 2010 in California), and talked with both Watts and Rheem. Both stated that the recirc pump should work better with these heat trap nipples removed. Interestingly, I went ahead and installed the recirc pump with the heat trap nipples still installed, and the recirc pump worked just fine (took about seven minutes to get hot water at the second-floor remote faucet). Being a perfectionist, and knowing that Watts had stated I that should remove them for the recirc pump to work optimally, I proceeded with doing so, and the pump works only marginally better (faster hot water). Removing the heat trap nipples was a bear, and once you start, you are committed, as you have to wrench directly on the threads of the short heat trap nipples. They'll come out, but require a ton of wrenching. Now, with plain copper nipples (that I also bought off of Amazon), the recirc pump gets hot water to the same remote faucet in about five minutes (versus the seven with heat trap nipples still installed). Moral of the story, and why I felt compelled write a review/post this, is that it may be worthwhile trying to install the recirc pump without removing the heat trap nipples, and then remove them only if the recirc pump doesn't work well for your unique application. Knowing what I know now, I probably would have just left the heat trap nipples in place. If you do remove them, remember that you should do a goose-neck configuration with the cold and hot water piping above the nipples in order for the piping to act as heat traps. I hope this is helpful. see lessWarning
By Lulu on December 28, 2018This device is not compatible with hot water heaters with a heat trap.This works with a heat sink!
By Michael M. on February 11, 2021My wife is so happy now! First, some of the reviews said that this device would not work on a hot water heater that has a heat sink. My hot water heater is four years old and has a built in heat sink and this recirculating pump works fantastic! Our master bath is the furthest distance from our water heater and it used to take 2 minutes and 30 seconds to get hot water to my wife’s sink where I installed the sensor. Now, it’s instant hot water and the pump is so quiet you can’t hear it and the timer is so easy to program! I fully recommend this pump! Also, it is so easy to install! see lessI am a little disappointed by the heat up time
By Bryan on April 6, 2015Works as designed. I am a little disappointed by the heat up time. Seems to take more time than I thought it would for the shower. Could be because the shower is beyond the sink where I located the recirculation valve. Still decreases heat up time some. see lessFalse Advertising
By M.P. on December 20, 2018This was advertised to work on any tank type water heater. However, it will not work with water heaters with heat traps. Most modern tank type water heaters have heat traps built in. There is no mention of this in any documentation, and only discovered after I had it installed. Now I have paid for the pump, the labor to install, and now labor to uninstall. The manufacturer didn't even try to make an excuse, much less even offer an apology. see lessNOT COMPATIBLE with all Hot Water Heaters - Check first!
By dancer25 on April 29, 2018Installation was easy in our new home. However, the water would not get more than luke warm. Thanks to those in the Amazon Community that tried to help me, thinking I had a bad sensor. But that was not the case. After days of phones calls between WATTS and Rheem (maker of our water heater), I found out from WATTS that this pump is not compatible with all makes/models of Hot Water Tanks. They new specifcally of my model and that the pump would not work. However, they do not mention that in the on-line specification - and they acknowdged this lack of information themselves when I asked. So, my recommendation is to check with WATTS to be sure your are good to go, first. You can actually start by looking at your User's Manual for your Hot Water Tank and look for the "Heat Traps" in the Nipple connecters on top.
This issue is the "Heat Trap" in the "Nipple" of the inlet and outlet of the Hot Water Tank. This Heat Trap is to keep the heat in the tank for efficiency. However, with this WATTS pump you are actually circulating the heat out, so defeats the purpose of the Heat Trap. Problem is, to remove the Nipple with Heat Trap from the Hot Water Tank and replace with a normal Nipple is next to impossible. Could not get the Nipples off with a large pipe wrench (even looked on YouTube - risky for damaging Tank). So, I plucked out the little "flaps" that are part of the Heat Trap (see picture) and the pump works better, but still not as advertised. I know removing the flaps likely voids the warranty on my Hot Water Tank, but I wanted the Hot Water! Disappointed.
I can only score a 3 for this pump becuase, 1) WATTS does not state anything about incompatiblity in the specification, and 2) it is not delivering the hot water as advertised in my case, even after taking out the flaps in the Heat Trap. I like the product, easy to install, was really excited about it, but disappointed. I have a couple more days to decide if I will return it. It is better to have pretty warm water rather than very cold water out of faucets for a long time, so maybe keep the pump. We'll see... see lessHeat pump
By The Stache on September 7, 2013Works quite well. Saves water. Our house has a very long water distribution line delivering water to the back bedrooms. The greatly reduces the time to deliver hot water. After pump installation, hot water delivery is near instantaneous.
Do watch the installation video. Installation is fairly straight forward with some cautions: installation with old pipes is problematic. I had to replace old pipes, which always presents its set of problems separate from the installation. see lesshappy wife, happy life
By Arthur W. Bethel on April 23, 2019What a game changer! Super easy to install and does what it says! 2 tips for ya...(1) make sure booster pump is in the “off” position and do NOT turn to “timer” until it has been plugged in, time set and timer adjusted. (2) make sure your water heater does not a “heat-trap” device installed in the hot water nipple prior to installing this booster (common amongst AO Smith, Rheem and Bradford White Water Heaters). If it does, remove the heat-trap device before installing. see lessheat valve - I want to correct some incorrect things others wrote
By DrPhil on February 10, 2021I just had this installed. I (unfortunately) did not buy from AMZ and (unfortunately) had it installed. Why? Some people talked about heat valves and therefore this unit didn't work. I wish I hadn't seen that because I would've done it myself and saved $400. according to the plumber, heat valves have NOT been used since the early 2000s (someone in another post said they're on the new ones). They did not work well he said. It took him one hour to install and HD has a great video showing the install to a whirlpool that's 5 years old. it seems to work really well and our shower is at least 50 feet from the water heater. No additional parts were needed. I have VERY basic understanding of plumbing and wish I'd done this myself. Good luck. see lessworks good
By dlh on August 6, 2020I had mine for over a year without any issue. My plumbing is plastic pipe running under the slab, it took about 3 gal of waste to get hot water at the kitchen sink. This system now gives me instant warm water and hot water shortly after. I have an electric meter on my hot water heater and after many months I have determined it adds 4kwh per day, my rate is 10.5 per kwh so for me about $13 mo, this is for 5 hours of use a day. Everybody's situation is different so this is just my example. Those saying they wont work with a water with a heat trap they are correct but the heat trap can easily be defeated. see lessSame o' Same o'
By Magic Man on March 10, 2019Second Watts recirc I have installed in a home and it solved my water wasting problems. One thing different, not Watts, is the water heater has nylon "heat trap" in the pipes that I took out because their purpose is to restrict flow. Easy to pry out and grab with pliers to pull loose. see lessVery nice product. It heats up probably after 3 cups ...
By Efren on December 3, 2016…It heats up probably after 3 cups of water. It is warm from the faucet where the sensor was placed.… see moreGreat Product
By MS on October 1, 2018Recently installed in residential application with copper pipe-in-slab with 40' run from hot water heater. Cannot comment on reliability. Installation was fast and simple. Solid build standard. Online trouble shooting guide was very clear and helpful for testing and working thru setup issues. Pump consumes only 25W while recirculating. My objective was to save water while increasing electric power consumption slightly. Found that electricity consumption was actually reduced due to shorter dishwasher and clothes washer cycle times.
Recommend the following:
- Remove heat traps from hot water heater before installing pump. Heat traps are typically red and blue plastic inserts with an internal ball or flap that are threaded into the water in and out lines on top of the hot water heater. Heat traps can sometimes throttle or prevent the recirculation flow. Heat traps are not required (actually counter-productive) if a recirculator is used.
- If installation is in a smart home, install the recirculator pump on a smart switch (instead of the included mechanical timer) to enable more flexible scheduling and to eliminate the need to reset timer after power interruptions.
- Clearly mark the four inputs/outputs of the control valve with tape or paint (red arrows for hot, blue for cold, etc.) prior to installation. The control valve is typically installed under sink, which makes reading the small black-on-black labels nearly impossible. The control valve has four inputs/outputs that must be installed correctly. see less
False advertising. Will not work with some hot water heaters.
By James L Moore on July 18, 2019This product will not work with newer hot water heaters that have heat trap nipples installed. I called Watts and the customer service rep. confirmed this. No where in the Watt's documentation that comes with the pump is this noted and even more significant is no where in the Amazon description is this mentioned. I installed this product as per the instructions and when it failed to perform it took a good bit of research to determine the problem. I have also spent a good bit of time researching a work around and there is none. The hot water heater mfg. informs me removing the di-electric heat trap nipple will void the warranty. Watts and Amazon should have made it clear this item will not work in some situations. Of course by the time I discovered this the window for return is closed. This is an expensive item and now I am out that money with no recourse. Amazon needs to fix this mess. I am getting more and more wary about buying larger ticket items from Amazon. see less