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reclaiming water lost from water heater
Yahoo Message Number: 150018
Larry and others who boondock a lot; If you could run a water line back  from a 'tee at the shower hose diverter, to the hotwater tank via a 'tee' at the  cold water inlet to the tank, then a small 12 volt pump could return cold, then  warming, then hot water back into the water heater, instead of having the water  heater suck up cold water from the main tank. About a 30 second timer could run  and shut off. A check valve would prevent the shower hose from pulling that  cooler water back out of the return hose. The only water 'lost' would be the  cold water in the actual shower head and hose.
I have a rear dinette TKB and the hot water (and cold going to  the heater) run in a channel through the floor near the water pump. More than  enough room to put in a 3/8" line and some insulation.
A little more hassle to winterize the coach.
I found this little pump that could be mounted under the  bathroom sink, and 12 volts is readily available. http://www.amazon.com/Solar-Water-Circulation-Brushless-Motor/dp A small timer should be available, or just a push button (human  timer) RonB with many higher priority projects....
As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: reclaiming water lost from water heater
Reply #1 –
Yahoo Message Number: 150027
"Larry and others who boondock a lot; If you could run a water line back from a 'tee at the shower hose diverter, to the hotwater tank via a 'tee' at the cold water inlet to the tank, then a small 12 volt pump could return cold, then warming, then hot water back into the water heater"

Ken

There are several different way of circulating the hot water. Most require a clear pathway, through the heated coach, for a return line to either the water heater, the water pump or the water tank.  We camp in the winter and cannot have an exterior water line, due to freezing temperatures. In our 23.5' FL, an acceptable pathway doesn't exist.
Considering that we would only save a maximum a two gallons of water, over  five days, it is hardly worth the effort and we still have the option of capturing the cold water.
If a clear path to the water tank or the inlet side of the water pump is available, no pump is needed.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: reclaiming water lost from water heater
Reply #2 –
Yahoo Message Number: 150039
There are several different way of circulating the hot water. Most require a  clear pathway, through the heated coach, for a return line to either the water  heater, the water pump or the water tank.  We camp in the winter and cannot have  an exterior water line, due to freezing temperatures. In our 23.5' FL, an  acceptable pathway doesn't exist.
Considering that we would only save a maximum a two gallons of water, over   five days, it is hardly worth the effort and we still have the option of  capturing the cold water.
If a clear path to the water tank or the inlet side of the water pump is  available, no pump is needed.

Larry


Ken I agree with Larry on most of his points.

There is one person in my camper and I can get by for 10 days on a tank. 5 gal a day??  In fact if I know that it will be longer I can get it down to 3 gal a day or less and that is not reclaiming the water at the lav. And that is taking a shower every day. For Larry I presume there are 2 people so there water usage will be up some.  I do not see where it is worth my while to go this rough. Sort of like the bat charging system that is going on at this time. If what they are saying about the splitter is true it will/should  work. But I have ONE jumper cable that is 24 foot and it will work every time. There are no parts to go bad or bat to be dead when I get it out of storage to use. No surprises. And all that work for some thing that you may never need or use is out of the question.

The BG unit he brought up I seen some years ago but never gave it any though.

This time I went to there web sight to study it. There is no way that it will work with out a return line. 55 years as a plumber tells me that. You must get the HW from the tank to the sink and return the cold to the tank unless you waste the cold water.  And this is not what they are doing.
What they are doing at a cost of $300 is changing the CW line into a return line for a short period of time. The use a solenoid valve and pump. When the water gets cold the solenoid valve opens and the pump starts. It takes the hot water from the tank brings it to the BG unit returns the cold water to the tank by way of the CW line. Once the temp of the water at the BG unit is reached it turns OFF and the use of the plumbing system is once again restored to the way it was.

Larry DIY (Ha Ha) can build this unit for less than $45 or maybe $10 depending what parts he has around the house. His pic on Flicker proves that.
 All the part have been shown here except for the DISH WASHER angle stops. You get two of them at Lowe's for $8.00 each? ? ? ?   The angle stops replace the tee's. Yes Ken you will not need the tee's. And the angle stops take up less room and less work. The whole unit can be built on the work bench and installed in one peace. You join the 2 DW outlets together and install the solenoid in this line. As Larry said above you may not need a pump. If once the solenoid opens and the hot water gets there in 5 or 10 minuets. or a time that you can live with there is no need for the pump. If you want it there faster install the pump. I think I would go with the pump right from the start.

There is no need to make any changes at the HW tank. Every thing is done at the lav. When and only when you want HW at the shower you turn on a switch, the solenoid opens and the pump (if used) starts and circulates the CW from the HW tank through the HW line and returns it through the CW line. After a few minutes you turn OFF the switch and press-to you have HW at the shower and you did not have to waste any water. The plumbing system is in use as it was when you got the MH from LD. The new HW return line is not needed and there is no worry of this one freezing because it is outside.


As for those that talked about running a new return water line. You DO NOT want to tie one into the water storage tank. This will heat the water in the storage tank and could start mold.

Do not tie it into the water line from the tank to the pump. The water will not move because there is a check valve in the pump that will stop the water from flowing by gravity.

The tee for this line has to be as close to the CW inlet to the HW tank to work best.

Dish washer angle stop      https://www.plumbingsupply.com/angle.html#3way

George

Retired plumber
Re: reclaiming water lost from water heater
Reply #3 –
Yahoo Message Number: 150042
All of these ideas to recirculate the water seem to be above my pay grade to effect, so a lower-tech solution seems more feasible.  I guess capturing a large amount of water is necessary for a shower, but for smaller uses of hot/warm water, why not keep a large-ish vacuum bottle on hand with heated water in it?  A pump pot would be one solution, but I fill just a quart container for use throughout the day.  If not all used up, there is usually still some in the morning that is warm enough for a comfortable hand/teeth wash.  If you preheat the vacuum bottle, and then fill it with really, really hot water, you will have sufficient hot water to mix with cold, as necessary, for warm-water uses all day long.  If you use it all up during the day, just heat some additional water on the stove and refill it.

At shower time, one could just route the cold water into a wide-mouthed container - something like a pitcher with a pouring lip - thence into a gallon jug for reuse in whatever manner presents itself.

For dishwashing, it is easy enough to fill one of the used (still hot/warm) cooking pans with water and heat on the stove for a few minutes, using that for the hot water to wash up the grubbiest of the dishes.  If you get it good and hot, and put a lid on it, the temperature should stay pretty high, and be about right for mixing with cold water to wash your dishes.

Rinse off the cleanest things first, and by the time you get into the task, the output from the water heater will be warm enough to wash and rinse the remaining dishes. Rubber gloves help with using water whose temperature might otherwise be uncomfortable - either too hot or too cold.

Virtual hugs,

Judie http://dorrieanne.wordpress.com
Re: reclaiming water lost from water heater
Reply #4 –
Yahoo Message Number: 150043
"As for those that talked about running a new return water line. You DO NOT want to tie one into the water storage tank. This will heat the water in the storage tank and could start mold." George

That really should be not be a problem unless the water was left recirculating for a long period. The run period should be just adequate to flush the hot water line and not long enough to add heat to the fresh water tank. Considering that it would be primarily used in the wintertime, the temperature of the fresh water tank is already very low. Heck, you might even build it to be used to warm the fresh water tank in very cold conditions.

I like the suggestion to use  dish washer angle stops, that would simplify the build.
More potential projects for next year

As for not connecting into the fresh water inlet line, why not? The return tee would be in the inlet line, before the water pump, where the return flow could either be re-pumped or flow back up the inlet line to the water tank, The return flow would be free to go either direction.
The check valves are in the pump. The inlet line, from the water tank to the pump, is free of them.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: reclaiming water lost from water heater
Reply #5 –
Yahoo Message Number: 150044
"As for those that talked about  running a new return water line. You DO NOT want to tie one into the  water storage tank. This will heat the water in the storage tank and  could start mold." George

That  really should be not be a problem unless the water was left  recirculating for a long period. The run period should be just adequate  to flush the hot water line and not long enough to add heat to the fresh  water tank. Considering that it would be primarily used in the  wintertime, the temperature of the fresh water tank is already very low.  Heck, you might even build it to be used to warm the fresh water tank  in very cold conditions.

I like the suggestion to use  dish washer angle stops, that would simplify the build.
More potential projects for next year

As for not connecting into the fresh water inlet line, why not? The  return tee would be in the inlet line, before the water pump, where the  return flow could either be re-pumped or flow back up the inlet line to  the water tank, The return flow would be free to go either direction.
The check valves are in the pump. The inlet line, from the water tank to the pump, is free of them.

Larry


I believe it was you the talked about installing a gravity return line for the HW tank but if outside it would freeze;

and there is no way it instill it inside that you can route it.

Systems like this have been used in larger homes for years (Gravity) and others had a pump. As you just said the check valve is in the pump. It is there to stop the city water pressure from filling the storage tank and running out the over flow. That check valve is always CLOSED. A lot of times this check valve has a VERY VERY slow leak and this is why you hear the pump kick on for just a second to build the pressure back up. When you hear the pump come on like this we think there is a leak in the plumbing system and we hunt and can not find it. I have that problem.
 In order for a gravity line to work there can not be a restriction in the line. If the gravity system if tided in before the pump the check valve in the pump will stop the flow from going to the HW tank because it is closed until the pump starts. Now you have another problem. The house side of the pump will never have pressure to stop the pump from running and the pump will run full time.

If you had it in the tank and it WOULD  flow you would be taking the water from the storage tank and run it into the water heater once again heating it and then by gravity or pump you would return it to the storage tank and keep heating all the water in the tank because it is going into the HW tank and heated and then returned to the storage tank to once again be run through the HW tank again and again. Now the water storage tank is a larege HW storage tank for the HW tank. After a while the water in the storage tank will be the same temp as the HW tank.
We use to do this with side arm heaters on boilers. You ran the CW through the side arm heater and stored it in an insulated tank so that you would not run out of HW.
So the return tee CAN NOT be before the pump.

No mater how you look at it the return tee must be on the out let side of the pump.

George

Retired plumber
Re: reclaiming water lost from water heater
Reply #6 –
Yahoo Message Number: 150045
Judie you are talking very much the way that I do it. Less the thermos. Being alone I do not have to capure the water at the lav. One person and 60 gal of water I can get by for 2 week by watching my use.
I only run the HW tank after I return to camp about 5 o-clock for a shower. I run it for 15 to 20 minutes unless I lose track of time. Which is most of the time. I quite often set a timer for 20 minutes but I'm out side with the ATV and friends and so do not hear the timer and the HW tank will turn off at 120.
I use a tea kettle for most of my hot water. If George and his wife are there we all cook/eat outside. That is the mens job. We get stuck with all the cooking. If alone I do not make coffee I have hot coco and cook inside. Tea Kettle. I put a little more than enough water in the kettle for coco and wash the dishes. Put a small amount of boiling water in the sink and add cold water to get a temp that I can do the dishes. Rinse with cold water. Very simple but it has worked for over 50 years.
 I could use the MW but then I have to start the gen. Some times I need to thaw some food and need to run the gen but I still use the tea kettle.

George

Retired Plumber.


 All of these ideas to recirculate the water seem to be above my pay grade to  effect, so a lower-tech solution seems more feasible.  I guess capturing a large  amount of water is necessary for a shower, but for smaller uses of hot/warm  water, why not keep a large-ish vacuum bottle on hand with heated water in it?   A pump pot would be one solution, but I fill just a quart container for use  throughout the day.  If not all used up, there is usually still some in the  morning that is warm enough for a comfortable hand/teeth wash.  If you preheat  the vacuum bottle, and then fill it with really, really hot water, you will have  sufficient hot water to mix with cold, as necessary, for warm-water uses all day  long.  If you use it all up during the day, just heat some additional water on  the stove and refill it.

At shower time,  one could just route the cold water into a wide-mouthed container - something  like a pitcher with a pouring lip - thence into a gallon jug for reuse in  whatever manner presents itself.

For  dishwashing, it is easy enough to fill one of the used (still hot/warm) cooking  pans with water and heat on the stove for a few minutes, using that for the hot  water to wash up the grubbiest of the dishes.  If you get it good and hot, and  put a lid on it, the temperature should stay pretty high, and be about right for  mixing with cold water to wash your dishes.

Rinse off the  cleanest things first, and by the time you get into the task, the output from  the water heater will be warm enough to wash and rinse the remaining dishes.  Rubber gloves help with using water whose temperature might otherwise  be uncomfortable - either too hot or too cold.

Virtual  hugs,

Judie
Re: reclaiming water lost from water heater
Reply #7 –
Yahoo Message Number: 150047
It is a good idea to have a spare water container for emergency, like when the water pump stops working and you have to use the bathroom. I carry 3 gals. in my Toad for emergencies, and 1 Gal. of distilled water for batteries, etc.

Bob
Re: reclaiming water lost from water heater
Reply #8 –
Yahoo Message Number: 150049
I live and breathe by my timer.  It fits in my pocket, and is happy to travel with me wherever I go.  ;->

Virtual hugs,

Judie http://dorrieanne.wordpress.com
Re: reclaiming water lost from water heater
Reply #9 –
Yahoo Message Number: 150052
It is a good idea to have a spare water container for emergency, like when  the water pump stops working and you have to use the bathroom. I carry 3 gals.  in my Toad for emergencies, and 1 Gal. of distilled water for batteries,  etc.

Bob


 I was at the flea market 5 years ago seen a new  water pump that I could use in the old Big Foot slide-in. I got rid of the BF in 2012 and bought the 2005 LD. Turns out the pump is the exact same pump as in the LD. When I made the 14 Week trip to Alaska I made sure that the sspare pump was on board. Since then the spare pump is always in the MH. As long as it is in the MH the old pump will never go out. But the day I put it back in the shed the pump will go out.
When we brake camp to head home we always drain the storage tank to get as much weight out of the camper. But never drain the HW tank. If I need water on the way home all I need to do is open the DRAIN valve on the HW tank where there is 5 gal. When I get home I then drain the HW tank. The MH NEVER sets at the house with water in the HW tank.

George

Retired plumber
Re: reclaiming water lost from water heater
Reply #10 –
Yahoo Message Number: 150076
"I guess capturing a large amount of water is necessary for a shower..."

Not really. I capture 700 ml (24 oz.) in a plastic bottle every morning when I shower, and use that to wash dishes with the rest of the day. 24 oz. run through the showerhead gets the water up to its full temperature. See this Eureka article for more. I shower and wash my hair daily with less than a gallon of water (not counting the 24 oz. that are put to good use).

Andy Baird

Travels with Andy
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: reclaiming water lost from water heater
Reply #11 –
Yahoo Message Number: 150077
"I live and breathe by my timer. It fits in my pocket, and is happy to travel with me wherever I go. ;->"

I just use my iPhone. I push the home button, say "Set a timer for 35 minutes," and Siri does the rest.

Andy Baird

Travels with Andy
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"