Instant Hot Water Line Recirculation Part 1

[@pjmazar4533]

Thanks for the video. I have comments from some who don't understand convection at all. I've done passive, (gravity), systems for many years with good results and happy customers. I had used a ball and spring type check valve in a vertical application with the spring removed. When pressure was applied, the ball would rise to close off that line. Now that valve is no longer available so I will give your setup a try on my next application. One thing that would probably help the setup would be to use copper plumbing, at least for the return lines if possible. Copper draws heat out of the water to cool it more rapidly. Naturally, all hot water feed lines should be insulated. Personally, I prefer copper for all my plumbing jobs.

[@fredgebauer8918]

I have installed two recirculating systems similar to this system using the same check value. The only thing I do different is drill an 1/8" hole in the center of the check value gate. This allows a small flow that makes it easier to create the gravity flow. Works great!

[@Lucas-vk8fz]

nice job! I bet the benefits of your modification collectively over time will be substantial... great idea and well executed...thanks for sharing

[@BrianK586]

I put my check valve in at a 45 deg angle. That way it is usually open which allows the circulation to occur and when the hot water tap is open, if water tries to go back up the re-circ line, the flow causes the check flapper to close. Worked for me. The recirc line works great and all fixtures on the hot water line now get almost instant hot water.

[@GrowingAnswers]

Brian K in my case, the valve housing was to large and the plastic valve I made floated to high which wouldn’t close with the flow alone. So the pin i installed holds it down at about a 45.

[@johntsouris2159]

You need to obtain or build a check valve using a floating plastic ball, vertically oriented. Ball must be food grade and able to handle 140F. Will never build up scale or have any other issue, and ball will not restrict convective flow at all.

[@markrainford1219]

They are called Anti-Gravity valves and are generally used on gravity primary circulation between a solid fuel stove and hot water cylinder.

[@MoNoShocks]

Instead of the swing valve, I believe you can use a regular gate valve where you drill a 1/8 inch hole in the gate. You open the gate valve to get the recirculation started and then you close the valve and the 1/8 in hole is enough to maintain circulation but too small for significant cold water to back flow.

[@pjmazar4533]

If only we had the time to experiment with every possible way of doing things to find the best results. You Tube sure helps to weed out the good and bad for all of us. In your case, have you tried your idea and what was the outcome?

[@youngpana203]

You should’ve used a spring check valve with a circulating pump

[@GrowingAnswers]

Young Pana this system is zero failure. No electricity, no pumps. Works without issue for nearly 30 years between both houses i have lived in.

[@MarkPerry-d4p]

I'm planning to install this system in my rancher with the water heater in the 5' crawl space. I have purchased two backflow preventers, one will be mounted vertically with the spring removed making it a normally open valve and only close on a backflow condition. One valve is a all brass construction and the other is a brass body with a polyethylene tappet inside. What are your thoughts on witch one to use? Also, this is a newer home and may have backflow preventers in the top of the water heater, would the hot out need to be removed?

[@GrowingAnswers]

If the backflow preventer on top of the water tank is brass or spring loaded, then it will need removed. You should use the one that has the polyethylene valve inside. Any backflow preventer with a metal valve will be too heavy for the unpressurized flow to work. Unless it’s mounted in the horizontal position. Metal Valves tend to seize some point though under low flow low pressure conditions.

[@brandonallen2584]

have you had the mating surface of the plastic swing valve and brass oxidize? love the idea

[@stevejohnson6053]

if system is on forced flow (pump) why would you ever let the return to expel heat?

[@columbusjuju5500]

Smart man

[@Dumped4ADildo]

You say spring valves won't work. I only use spring valves, they tend to have less issues. I like your creativity molding a new swing door. However the body will still calcify and corrode and aside from the minerals it pulls form the water which can be solved in other ways, you have brass to copper so you have dissimilar metals creating electrolysis which is the most common cause of buildup and corrosion. That could be solved by using cpvc male ended nipples. You can use cpvc check valves and eliminate the metal all together the best route. The big problem I see with your fix is not only will the body continue to have build up and corrosion but that plastic you molded will warp from the heat of the hot water. It may appear to work fine for some some time before you have a noticeable problem but it will begin to destroy you efficiency immediately. Also and the end of the would not have been easier to just replace a ten dollar valve rather than spending all that time attempting to out think the engineers?

[@markrainford1219]

Why are copper and brass dissimilar? Brass is a copper alloy.

[@merrittmontgomery3495]

Can you explain how you made the mold ? Please

[@GrowingAnswers]

With the existing flap and plaster

[@GrowingAnswers]

With the existing flap and plaster

[@merrittmontgomery3495]

Do you have more detail on how to make with Plaster ? Please

[@mr.brownplumbing]

Pvc piping is not rated for hot side application. Granted you have transitioned to cpvc after the check closer to the hot water heater. Idk i think inspection would fail?

[@GrowingAnswers]

It’s all cpvc and pex.

[@sabrialhawwash2571]

It’s not going to be easy to make that piece can I use a plastic Check valve

[@GrowingAnswers]

The plastic valve with female threads has a tendency to crack. They don’t make them in cpvc last I checked.

[@sabrialhawwash2571]

@@GrowingAnswers thank you for your help I’m gonna work on it today and let you know

[@DownunderGraham]

This makes perfect sense to me in regards to saving water. I am looking for a solution that allows me to get rid of one of my hot water heaters. I have two. One is at one end of the house and services the two bathrooms (400L), the other is at the other end of the house and services the laundry and kitchen (80L). I assume that the second hot water heater was installed to avoid having to run a really long hot water line from one end of the house to the other. I want to go to a single large hot water heater that I will be heating with evacuated tube solar. For me the passive thermosiphon system described here would be perfect so long as it doesn't cause a problem with the evacuated tube system. I think I might give it a try.

[@tw7204]

so you say you didn't buy the PVC swing check because it needs to be chlorinated but you used a plastic cap off of a foam insulation can kind of a weird thought process there

[@GrowingAnswers]

Black Gold it’s pvc. The swing valves that are all plastic including the housing can be problematic.

[@Forge5894]

Interesting repair method. Thank you for posting this video!

[@NicolasWill]

Very helpful. Thanks for making this video.

[@truth6600]

You should have put an expansion tank.

[@GrowingAnswers]

I did. It goes on the cold side

[@TheLimbReaper]

For what it's worth this all makes perfect sense to me. This may be a viable solution to my second floor bath; even more so if I can maybe fish PEX tubing or PVC up the wall as the return line. Hundred year old house with renovations. Maybe.

[@readytemp4473]

And you prevent water circulating 24/7 through your pipes and water heater how?

[@GrowingAnswers]

I'm not sure what your question is regarding. The best way I can answer is that when you turn the hot water on at the faucet, you want the swing valve to close to water only flow out the top of the tank as designed. You want the swing valve to stay open all the time to allow water to naturally circulate hot water to the points of use. Judging by your avatar, I'm not sure if you are being rhetorical based on misinformation perhaps.

[@readytemp4473]

"You want the swing valve to stay open all the time to allow water to naturally circulate hot water" all-the-time=continuous water heater demand

[@GrowingAnswers]

Redy Temp Actually it hardly has any effect. This is a more common practice the some people realize. All my hot water pipes are very well insulated and the circulation happens so slow that the volume of water heated is hardly a gallon worth. Before I replaced my tank, my gas bill was around 25 for summer. The new tank is 10 gallons larger and the bill is between 25-30 in summer. Because of hot water usage for daily life it has constant demand just by turning on a faucet for a minute or 2. The tank sitting without demand hardly kicks on at all. Letting the water run for a full minute to get hot at the spicket is less efficient than having it already there. The demand is about the same when averaged out, but wastes less water.

[@readytemp4473]

I think you need to lay off the sauce, your not make'n any sense.

[@GrowingAnswers]

Redy Temp What don't you understand?

[@evenflow3256]

Spring loaded check is best

[@GrowingAnswers]

That won’t work unless a pump is installed. There is no pressure in this. It’s convectional free flow.

[@shawnd567]

I'm about to add a recirculation line on my home. I'm reading I can just tee into the cold water inlet since it goes down a dip tube. Will this work or will it be much better doing it through the drain?

[@GrowingAnswers]

shawn d you need to feed it into the bottom for better circulation. And remember to use a check valve.

[@marymyers3560]

Check valve

[@KWKloeber]

Oh? Lime scale doesn't build up on plastic? Really? Think again. I've seen plastic (pvc, abs, etc) check valves, pipes, pumps, completely blocked with lime scale.

[@pilotoelguapo]

good idea!

[@evenflow3256]

You're mixed up bro

[@larrycurrier290]

this guy don't know s*** from Shinola that hot water dip tube that goes in that tank does not blast water into the bottom of the tank are you'd have sediment throughout the whole system the hot water dip tube is actually perforated all the way down so that it spreads out the introduction of cold water evenly throughout the tank and if I understand what this gentleman started out saying is he gravity feeds hot water up through his system so the hot water is there all the time I can imagine his utility bill for this tank is way more than it should be and creating heat in your house in the summer time to offset it with an air conditioner more utility cost and that little valve you're playing with their is called a swing check

[@GrowingAnswers]

LARRY CURRIER working perfectly for years. Old tank was 40 gallon and had cost $27/month during summer with NO circulation system and ONE person living. New tank is 50 gallon and costs $35/month during summer WITH hot water circulation and TWO people living. You do the math...

[@larrycurrier290]

Growing Answers it may work fine but your explanation of this piece of equipment is not correct in some aspects you're going to make videos got to know what you're talkin about

[@arrow09]

The dip tube is not perforated... that would defeat the purpose of the dip tube. Its purpose is to direct the water to the bottom of the tank, then it forces the hot water (since hot rises) out the top of the tank.

[@pjmazar4533]

I scrap old tanks and have never found a perforated cold line supply. The idea behind water coming to the bottom of the tank is to prevent sediment. Some tanks are built with piping that will swirl the water to help keep it clean. As far as costs, I think a detailed study would have to be done to determine energy cost to heat versus cost of wasted water. Bottom line, it's really the convenience of have hot water at the tap.

[@willis23jm1]

You are confuse.... dont try to explain that which you dont know

[@GrowingAnswers]

willisjam fire been using it for 6 years and know exactly how it works and it also works perfectly. My father has his set up and it’s worked for well over 20 years.

[@HotWaterLobster]

It's much easier to just install a Hot Water Lobster instant Hot Water Valve.

[@pjmazar4533]

I think you've missed the point of a gravity system. Your lobster may be an easier way but more costly. Also, you need to have a power supply under your sink.

[@Vince-e2w9w]

You may not have done all your research (Physics 101). By "gravity system", you may mean thermal convection (hot water rising above cold water). Thermal convection is caused by the difference in pressure created when water is heated (expanding the water molecules). Expanding the water molecules, by heating the water, makes then lighter than cold water molecules causing hot water to rise above the sinking cold water (the cold water having condensed and heavier molecules). As the hot water molecules expand and rise to the top of the water tank, a slightly higher pressure is created at the top of the water tank than at the bottom the water tank (cold water having condensed and heavier molecules). The thermal convection is what circulates hot water through an open plumbing system. The Hot Water Lobster Recirculation Valve uses the thermal convection generated within standard water tank type water heaters to circulate hot water. It does not require any electricity or pumps to operate. For under $200 it is an inexpensive solution with a very easy, under sink installation that anyone can install. I hope this helps your understanding.

[@TheNorthsquad]

silliest thing I ever saw get a small re-cirulating pump and be done with it.

[@GrowingAnswers]

TheNorthsquad this requires no power to run, no moving parts. been using this method for over 20 years without flaw. Every installment in the house has warm water the second it’s turned on. recirculating pumps are point of use only. if you have many faucets and showers, you’d still need to run a return line like this to circulate to all of them. And at that point you’d no longer need a pump. The system is self sustained with convention alone. with or without a return line, the gas bill didn’t change. and by a flow trickling back through the bottom of the tank it helps to circulate the water and reduce buildup of mineral deposits helping prolong the life of the tank.