Hot water recirc systems
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59 wagon man
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Re: Hot water record systems
volume maybe a little tough
volume maybe a little tough
jmpacker13
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Re: Hot water record systems
Try looking into a recirculating system such as the Bell & Gossett wireless ecocirc plumbing pump. Uses a pump at the hot water tank and a wireless valve at the farthest fixture to create a recirculating loop back to the tank.
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Try looking into a recirculating system such as the Bell & Gossett wireless ecocirc plumbing pump. Uses a pump at the hot water tank and a wireless valve at the farthest fixture to create a recirculating loop back to the tank.
Sent from my iPhone using Tapatalk
sweetk30
Well-known member
Re: Hot water record systems
i went threw the problem of almost 5 min to get hot to the kitchen sink .
the last owner installed a on-demand hot water unit at the other end of the house . then feed it threw the rats nest of copper pipe from years of add on mix-n-match and 1/2 or 3/4 then back to 1/2 and then 3/4 till it hit the 1/2" line to the sink feed .
i re-plumbed the house from scratch with pex and did a manifold design . the manifold is 3/4 off the hot water tank i put in over the worn out on-demand unit . then each feed of of the 3/4 is 1/2" . the sink feed is a direct shot off the end line of the manifold closest to the inlet from the hot water tank .
now is maybe 45 sec max average 25-35 sec for warm then full hot .
you need to use smaller pipe / lines to speed up the flow as there is less storage capacity over the bigger line . also you ever notice the tiny line going in to the fixture ?
other option i did for 2 years before i re-plumbed and did a hot water tank was a mini 5 gal hot water tank that plugged in to 110 volt and was in the basement pump room directly below the kitchen sink . this also helped a lot until the hot water got there from the old on-demand unit . and the electric bill hardly jumped from its use .
so glad i fixed the rats nest of old copper pipe and mix/match of sizes . i got the basement bathroom area to do yet of old copper mess but then it will be done .
hope this real world info of my problems help you fix yours .
i went threw the problem of almost 5 min to get hot to the kitchen sink .
the last owner installed a on-demand hot water unit at the other end of the house . then feed it threw the rats nest of copper pipe from years of add on mix-n-match and 1/2 or 3/4 then back to 1/2 and then 3/4 till it hit the 1/2" line to the sink feed .
i re-plumbed the house from scratch with pex and did a manifold design . the manifold is 3/4 off the hot water tank i put in over the worn out on-demand unit . then each feed of of the 3/4 is 1/2" . the sink feed is a direct shot off the end line of the manifold closest to the inlet from the hot water tank .
now is maybe 45 sec max average 25-35 sec for warm then full hot .
you need to use smaller pipe / lines to speed up the flow as there is less storage capacity over the bigger line . also you ever notice the tiny line going in to the fixture ?
other option i did for 2 years before i re-plumbed and did a hot water tank was a mini 5 gal hot water tank that plugged in to 110 volt and was in the basement pump room directly below the kitchen sink . this also helped a lot until the hot water got there from the old on-demand unit . and the electric bill hardly jumped from its use .
so glad i fixed the rats nest of old copper pipe and mix/match of sizes . i got the basement bathroom area to do yet of old copper mess but then it will be done .
hope this real world info of my problems help you fix yours .
wssix99
Well-known member
Is this an option for you? It requires plumbing a new set of lines in the walls and also insulating the pipes. (If you don't insulate, your costs will go way up to operate the system.)
If you have the opportunity to do that, it's a great luxury. You can create a passive system that uses gravity to do a slow re-circulation, or you can put in a re-circulating pump with a timer. (IMO - The timer is a necessity to make operation of the pump systems somewhat economical.)
Dustball
Well-known member
Re: Hot water record systems
I was looking at the TacoGenie last week. It's an on-demand recirc system where you'd push a button or have a motion sensor start the pump until hot water reaches it then it'll shut off.
https://www.tacocomfort.com/products/systems/instant_hot_water/genie/index.html
No new plumbing, just need an outlet below the sink.
I was looking at the TacoGenie last week. It's an on-demand recirc system where you'd push a button or have a motion sensor start the pump until hot water reaches it then it'll shut off.
https://www.tacocomfort.com/products/systems/instant_hot_water/genie/index.html
No new plumbing, just need an outlet below the sink.
Re: Hot water record systems
I have had a variation of a gravity return recirculation loop on my last three homes.
No moving parts, no maintenance, works perfect with hot water available at the distant fixture in a few seconds. Cost of gravity return is the cost of the pipe. With tank system NG the cost is pennies per month, actually might be saving money as it avoids running the water for a minute or two or more to get hot water to the shower ?
If I was try to install a gravity loop as a retro fit........would use PEX to control the cost and ease of routing. Gravity loops works best with the hot water tank in the basement. Gravity loop does not work with tankless.
I have had a variation of a gravity return recirculation loop on my last three homes.
No moving parts, no maintenance, works perfect with hot water available at the distant fixture in a few seconds. Cost of gravity return is the cost of the pipe. With tank system NG the cost is pennies per month, actually might be saving money as it avoids running the water for a minute or two or more to get hot water to the shower ?
If I was try to install a gravity loop as a retro fit........would use PEX to control the cost and ease of routing. Gravity loops works best with the hot water tank in the basement. Gravity loop does not work with tankless.
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Re: Hot water record systems
My daughter moved to a new to them house last Dec. The water heater was in the garage and with kitchen and M BR above the kitchen. There was 100+ feet of 3/4" copper (2.5 gal) hot water line to get to the kitchen. Ridiculous. I pulled the old tank and put in a Rinnai tankless with their wireless control putting a wireless push button under the lip of the upper cabinet next to the kitchen sink and a wireless motion sensor in the master bath. I did the crawl in the 16" crawl space to run a dedicated 3/4" pex recic line. With the dedicated recirc line it now takes less than 12 sec to get hot water and after the last drought the water waste is dramatically reduced. That wireless control can be added to any of their water heaters other than the "Value" series made since '06.
My daughter moved to a new to them house last Dec. The water heater was in the garage and with kitchen and M BR above the kitchen. There was 100+ feet of 3/4" copper (2.5 gal) hot water line to get to the kitchen. Ridiculous. I pulled the old tank and put in a Rinnai tankless with their wireless control putting a wireless push button under the lip of the upper cabinet next to the kitchen sink and a wireless motion sensor in the master bath. I did the crawl in the 16" crawl space to run a dedicated 3/4" pex recic line. With the dedicated recirc line it now takes less than 12 sec to get hot water and after the last drought the water waste is dramatically reduced. That wireless control can be added to any of their water heaters other than the "Value" series made since '06.
mires
Well-known member
Re: Hot water record systems
I put these in for customers all the time and they love them. No need to run a dedicated return line.
https://www.amazon.com/dp/B000E78XHG/?tag=atomicindus08-20
I put these in for customers all the time and they love them. No need to run a dedicated return line.
https://www.amazon.com/dp/B000E78XHG/?tag=atomicindus08-20
kbuhagiar
Well-known member
Re: Hot water record systems
Help me out here...I always thought that you need to have a return line for something like this. How does the water loop back to the heater?
Help me out here...I always thought that you need to have a return line for something like this. How does the water loop back to the heater?
mires
Well-known member
Re: Hot water record systems
You install a sensor valve at the furthest fixture from the water heater. (Under a sink is easiest) and it uses the cold line for the return. Here is a PDF of the brochure that explains it well.
https://www.watts.com/dfsmedia/0533dbba17714b1ab581ab07a4cbb521/29556-source/PF-IHWRS.pdf
You install a sensor valve at the furthest fixture from the water heater. (Under a sink is easiest) and it uses the cold line for the return. Here is a PDF of the brochure that explains it well.
https://www.watts.com/dfsmedia/0533dbba17714b1ab581ab07a4cbb521/29556-source/PF-IHWRS.pdf
Re: Hot water record systems
Our current house (16+ years now) has a dedicated return line with a Grundfos pump and if something ever happened to the pump, I would IMMEDIATELY order a replacement - they work that well and I wouldn't want to be without it.
A basic systems run on a programmable timer. A step up would be to incorporate a thermostat that clips on the return line. Once the temp in the return line reaches the setpoint, it turns off the pump.
I think the way to go is with the 'on-demand' type system. The pump never runs until it is activated - either by a push button switch, remote control, motion sensor, whatever. Our recirc pump is the main reason why I got involved with Z-Wave devices. We started out with little remote controls in each bathroom and you would push a button to turn the pump on or off. When I got a more advanced system (HomeSeer) I could set it up so that once it was turned on, the pump would only ever run for about 4 minutes before automatically shutting off. Now with Amazon Alexa, we don't need the remotes, we just have to say - "turn on the hot water" water, and we are good to go
here is what the thermostat I was talking about looks like
Our current house (16+ years now) has a dedicated return line with a Grundfos pump and if something ever happened to the pump, I would IMMEDIATELY order a replacement - they work that well and I wouldn't want to be without it.
A basic systems run on a programmable timer. A step up would be to incorporate a thermostat that clips on the return line. Once the temp in the return line reaches the setpoint, it turns off the pump.
I think the way to go is with the 'on-demand' type system. The pump never runs until it is activated - either by a push button switch, remote control, motion sensor, whatever. Our recirc pump is the main reason why I got involved with Z-Wave devices. We started out with little remote controls in each bathroom and you would push a button to turn the pump on or off. When I got a more advanced system (HomeSeer) I could set it up so that once it was turned on, the pump would only ever run for about 4 minutes before automatically shutting off. Now with Amazon Alexa, we don't need the remotes, we just have to say - "turn on the hot water" water, and we are good to go
here is what the thermostat I was talking about looks like
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jmpacker13
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The Bell & Gossett system is still the way to go for cross connect recirculation. The pump stays at the water heater or basement with only a wireless cross-over valve under the vanity. No buttons no noise. IMO
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Dustball
Well-known member
Re: Hot water record systems
This animation helps-
When the pump turns on, it draws water out of the hot water line and pumps it into the cold water line. The cold water line then refills the water heater tank and this continues until the hot water line reaches a temperature set point where the pump shuts off. The draw of the hot water line and pumping into the cold water side happens simultaneously and water pressure is maintained so no water is drawn from the city/well water supply.
This animation helps-
engineer2
Well-known member
Re: Hot water record systems
I put one in my house and used the plumbing vent chase to get the 1/2" copper return line up to the second floor bathrooms. I happened to have the walls open for a bathroom remodel, so it was pretty easy. Used a Taco pump with the timer and temperature sensor. I would not use Taco pumps again. They have an o-ring that is prone to failure, which will cause a major flood.
I put one in my house and used the plumbing vent chase to get the 1/2" copper return line up to the second floor bathrooms. I happened to have the walls open for a bathroom remodel, so it was pretty easy. Used a Taco pump with the timer and temperature sensor. I would not use Taco pumps again. They have an o-ring that is prone to failure, which will cause a major flood.
yatg
Well-known member
Re: Hot water record systems
Possible issue with these is that they have a fine mesh screen in the return fitting. Any **** in your water will clog the screen.
Possible issue with these is that they have a fine mesh screen in the return fitting. Any **** in your water will clog the screen.
rust in the eye
Well-known member
Re: Hot water record systems
I see the sensor valve # 596816. Is this required or is it a different solution?
I'm unclear on it's function.
Thanks
this looks like a good solution for a friend who has this problem in his new home.
I see the sensor valve # 596816. Is this required or is it a different solution?
I'm unclear on it's function.
Thanks
joe_padavano
Well-known member
Re: Hot water record systems
I installed a recirc system with a dedicated return line to the hot water heater. I like it a lot. PEX made it easy to snake the return line into place. I am skeptical of the systems that use the cold pipe as the return for several reasons. First, you typically do not drink hot water from the tap. The hot water can have a taste to it from the water heater. Second, in the summer, you'll have to run your cold water to get the temp down.
I installed a recirc system with a dedicated return line to the hot water heater. I like it a lot. PEX made it easy to snake the return line into place. I am skeptical of the systems that use the cold pipe as the return for several reasons. First, you typically do not drink hot water from the tap. The hot water can have a taste to it from the water heater. Second, in the summer, you'll have to run your cold water to get the temp down.
Re: Hot water record systems
I had a recirc on my last house. It was a 4 story monstrosity. Instant hot water on the top floor. I absolutely loved it. It had a dedicated pump and return line. Occasionally the pump would get air bound if the power dropped and it would not work. Without the recirc, it took forever to get hot water upstairs.
It did run up my gas bill a little, but it dropped my water bill a good bit. Well worth it, especially in the winter.
I had a recirc on my last house. It was a 4 story monstrosity. Instant hot water on the top floor. I absolutely loved it. It had a dedicated pump and return line. Occasionally the pump would get air bound if the power dropped and it would not work. Without the recirc, it took forever to get hot water upstairs.
It did run up my gas bill a little, but it dropped my water bill a good bit. Well worth it, especially in the winter.
dcg9381
Well-known member
Re: Hot water record systems
It's gonna depend on your use case. I wouldn't want a re-circ system with an instant-on propane/NG/Electric water heater. I'd want a push-button recirc system.
Other options - as mentioned - point of use.
Electric instant on - these take a LOT of power.
Depends on your water bill, your water availability, electric bill / gas bill, etc.
It's gonna depend on your use case. I wouldn't want a re-circ system with an instant-on propane/NG/Electric water heater. I'd want a push-button recirc system.
Other options - as mentioned - point of use.
Electric instant on - these take a LOT of power.
Depends on your water bill, your water availability, electric bill / gas bill, etc.
wssix99
Well-known member
Re: Hot water record systems
That's what I thought at first. Fortunately, we put the extra lines in and could just pop in the pump after the fact...
It's all about the run from the heater to the faucets. We have a string of faucets fed by a 1" water line and it takes FOREVER for hot water to get to the last faucet on the chain. Even if we had a push button system, we'd be waiting for an eternity.
That's what I thought at first. Fortunately, we put the extra lines in and could just pop in the pump after the fact...
It's all about the run from the heater to the faucets. We have a string of faucets fed by a 1" water line and it takes FOREVER for hot water to get to the last faucet on the chain. Even if we had a push button system, we'd be waiting for an eternity.
DRP6833
Well-known member
Re: Hot water record systems
I installed a system in a previous house. You definitely want a dedicated return line, otherwise if the pump kicks in while you're in the shower, the cold water line is suddenly filled with warm water instead of cold water and you could get scalded.
I installed a system in a previous house. You definitely want a dedicated return line, otherwise if the pump kicks in while you're in the shower, the cold water line is suddenly filled with warm water instead of cold water and you could get scalded.
redmondjp
Well-known member
Re: Hot water record systems
As mentioned in one post above, the small electric tanks are another way to skin this cat. I put a 2.5 gallon tank inside our dual-sink bathroom vanity, for the sinks only, and I have a 5 gallon unit (wish it was the 6.5 gallon instead) underneath the kitchen sink for the sink and the dishwasher. I have an on-demand natural gas heater for the rest of the house.
As mentioned in one post above, the small electric tanks are another way to skin this cat. I put a 2.5 gallon tank inside our dual-sink bathroom vanity, for the sinks only, and I have a 5 gallon unit (wish it was the 6.5 gallon instead) underneath the kitchen sink for the sink and the dishwasher. I have an on-demand natural gas heater for the rest of the house.
Re: Hot water record systems
Adding additional units ? Not sure that makes any sense ?
NAT GAS water heating is literally dirt cheap .........why would you want to add electric hot water devices in any shape or form ? If it’s an all electric home, guess it makes no difference where the energy is consumed.
If you have NAT GAS in the home .........Some sort of recirculation system is simple and affordable way to address the distant faucets.
What’s DIRT cheap ? my NAT GAS cost to heat water with a conventional 50 gal. tank is less than $10/month. That $10 also runs the dryer and gas cook top.
Adding additional units ? Not sure that makes any sense ?
NAT GAS water heating is literally dirt cheap .........why would you want to add electric hot water devices in any shape or form ? If it’s an all electric home, guess it makes no difference where the energy is consumed.
If you have NAT GAS in the home .........Some sort of recirculation system is simple and affordable way to address the distant faucets.
What’s DIRT cheap ? my NAT GAS cost to heat water with a conventional 50 gal. tank is less than $10/month. That $10 also runs the dryer and gas cook top.
redmondjp
Well-known member
Re: Hot water record systems
I'm not sure where you live, but I would not call my natural gas water heating dirt cheap. And there is the heat loss to the environment of having my copper pipes hot all of the time from the circulating system. I lose very little heat from the tiny tank underneath the sinks. And in my case, adding the two tanks was simpler than trying to get some sort of recirculation system set up. To each their own.
I'm not sure where you live, but I would not call my natural gas water heating dirt cheap. And there is the heat loss to the environment of having my copper pipes hot all of the time from the circulating system. I lose very little heat from the tiny tank underneath the sinks. And in my case, adding the two tanks was simpler than trying to get some sort of recirculation system set up. To each their own.
Re: Hot water record systems
Electricity is three times the cost of NAT GAS is my area. So yes, it pays to figure that into one’s decisions, usage and design. Estimate the heat loss cost to be less than .30-.50 per month but could actually be far less to net gain by not running the water for an extended period to fill the pipes with warm water with each use. That’s the concept and goal of the recirculation system comfort and convenience.
Electricity is three times the cost of NAT GAS is my area. So yes, it pays to figure that into one’s decisions, usage and design. Estimate the heat loss cost to be less than .30-.50 per month but could actually be far less to net gain by not running the water for an extended period to fill the pipes with warm water with each use. That’s the concept and goal of the recirculation system comfort and convenience.
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Todd.Brock
Well-known member
I have been planning on doing one of these when I replaced the water heater with a tankless. Had a tank failure last weekend that forced my hand for another tank model from HD on a Sat night. Totally forgot to pick up a pump. Dang it.... now I’m going to have to redo it. I redid our master bath and put the rain shower in the ceiling and it seems like it takes FOREVER.
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dcg9381
Well-known member
Re: Hot water record systems
I'll be doing this (installing a recirc line). I was under the assumption that the push button systems start the re-circ process for a limited amount of time?
I'll be doing this (installing a recirc line). I was under the assumption that the push button systems start the re-circ process for a limited amount of time?
Re: Hot water record systems
So with a system like this, you would end up with "warm" water in your cold water lines, correct? Because it's circulating the previously heated water back to the water heater. You would then have to wait for cold water to get to the faucet (drink of water, brushing teeth)
Our master bathroom is on the far end of the house too. Would be nice to have at least a little warm water for washing hands. I have toyed with installing a small point of use heater under the sink, but not sure if that's worth the effort either?
So with a system like this, you would end up with "warm" water in your cold water lines, correct? Because it's circulating the previously heated water back to the water heater. You would then have to wait for cold water to get to the faucet (drink of water, brushing teeth)
Our master bathroom is on the far end of the house too. Would be nice to have at least a little warm water for washing hands. I have toyed with installing a small point of use heater under the sink, but not sure if that's worth the effort either?
kj_mustang
Well-known member
If you can get into the crawl space or basement and run a dedicated return line of pex, it works very well with my DHW storage tank. I use a Grundfos recirculating pump with a separate digital timer, set to go off a few times a day right before my family's peak usage times.
A dedicated line is nice -- make sure they are insulated. I have used a timed pump w/ temp sensor.
I'm trying to figure out what's best for my new build.
I think having an occupancy sensor is a good idea depending on the actual speed of the hot to the tap .. I was thinking for a bathroom this would be a god idea. I have also done a control off the main light .. both have issues IMO.
The timed was for a kitchen ... we ran it early morning and in the evening M-F and all day during the weekends. The sensor was fixed --- it's actually under the max of the water heater but it's hot enough that you need a mix of cold for washing hands etc ... and the full hot is quick to come because the line is line almost there.
I'm trying to figure out what's best for my new build.
I think having an occupancy sensor is a good idea depending on the actual speed of the hot to the tap .. I was thinking for a bathroom this would be a god idea. I have also done a control off the main light .. both have issues IMO.
The timed was for a kitchen ... we ran it early morning and in the evening M-F and all day during the weekends. The sensor was fixed --- it's actually under the max of the water heater but it's hot enough that you need a mix of cold for washing hands etc ... and the full hot is quick to come because the line is line almost there.
Chevota Guy
Well-known member
Our 3 yr old home has a tankless water heater and we had a recirc system intall during the build. They used Pex everywhere and it has a dedicated return line. We had a problem with our ACT D'Mand Controls S3-100 system which was was driving us nuts. Three locations had doorbell buttons to trigger the pump but it would shut off after only a few seconds.
The problem turned out to be their temperature sensing method to shut the pump off. ACT uses a "Delta T" that senses temperature rise rather than an a specific temperature. They tout that as being better than timers or absolute temperature sensors, but not in our case. Since we live in the desert, the return line which ran above the garage in a non insulated area would often remain quite warm through the night. Then when we called for the pump to run, the slight rise in temperature would shut the system down before it had a chance to charge the line with hot water.
After about six attempts to fix it, they wound up changing our control board to one with a 45 second timer and disconnecting the temp sensor altogether.
It has worked reliably since then but if you have any type of condition that would falsely trigger a delta-T temp sensor, then I'd stay away from ACT D'Mand systems.
The problem turned out to be their temperature sensing method to shut the pump off. ACT uses a "Delta T" that senses temperature rise rather than an a specific temperature. They tout that as being better than timers or absolute temperature sensors, but not in our case. Since we live in the desert, the return line which ran above the garage in a non insulated area would often remain quite warm through the night. Then when we called for the pump to run, the slight rise in temperature would shut the system down before it had a chance to charge the line with hot water.
After about six attempts to fix it, they wound up changing our control board to one with a 45 second timer and disconnecting the temp sensor altogether.
It has worked reliably since then but if you have any type of condition that would falsely trigger a delta-T temp sensor, then I'd stay away from ACT D'Mand systems.
scottydosnntkno
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- Aug 8, 2010
- Messages
- 670
There are many systems that the the farthest ends of your main run together, so you don’t have to redo everything.
They can also be remotely controlled with an app, that you set your times of when it should run (6-8 am and 5-9pm for example). Or they have smart controllers built in that sense the same thing. Or they have remote switches that you get up in the morning, push the button, take a piss and thirty seconds late when you turn the shower on it’s instant hot
eastbaysubaru
Well-known member
Re: Hot water record systems
I installed one of these about a year and a half ago. Works great! Cold water can be a bit warm initially, but it's a no-brainer trade-off when the hot water comes out in 15 seconds rather than 45sec. to 1+ min.
-Brian
I installed one of these about a year and a half ago. Works great! Cold water can be a bit warm initially, but it's a no-brainer trade-off when the hot water comes out in 15 seconds rather than 45sec. to 1+ min.
-Brian
BD1
Well-known member
I ran a gravity return line as mentioned by others. No pump, add tee where water heater drain is. Drain moved to tee and return tied into tee. Insulating pipe will help.
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dcg9381
Well-known member
Anyone recommend a push-button-on recirc system? Don't want a timer.
Taco makes one with the capability ... but it has other options that push the price up to around $400.
I would like a system with a timer and the button ..