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Topic: Hot Water Recirculation (Read 3103 times) previous topic - next topic

Re: Hot Water Recirculation

Reply #25 –
The Aquahot sensor fits in behind the panel on the AH where the thermostats are mounted. (There is a panel that comes off above the wiring panel to revel the thermostats.) It is a snug fit, once in place and the cover plat is back on the stay in place.

There is an unused port on the hot side of the manifold where I added a brass T before the new recirculator line.  The sensor fits in the T.  It measures the temp of the water when it is recirculating but since water is not going by when hot water is used any other time I am probably going to move it to the hot water line coming from the AH into the manifold.  That water is usually 115-120° the mixing valve at the AH is set for 120°. 

This really lets me see what the AH is doing.  For most users most of the time you don't need to leave the 120 on all day or the diesel at all. 2-4 hrs a day for 120 is enough.  You have to figure out for yourself what works for you.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Hot Water Recirculation

Reply #26 –
I have a Berkey in my coach.  I have a nice looking pitcher that I fill while waiting for hot water and put it into the Berkey. No wasted water, and a lot less technical.  My system takes about 2 quarts of water to get hot.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: Hot Water Recirculation

Reply #27 –
I used 2 aquarium pumps, with a timer, one for the kitchen sink and one for the shower. I teed into the hot water line just before
the valves and returned the water to the cold water line with a check valve. I push the switch a minute before I want to use hot
water and half a cup of water is hot and the shower just needs to clear the water from the shower hose and the bathroom sink
is probably a cup of water. The pump is put in the line between the tee and the check valve.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Hot Water Recirculation

Reply #28 –
My temperature senders are located behind the thermostat plate on the Aqua Hot, behind a cover. The other is on the hot water side of the manifold, each needs a ground wire.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Hot Water Recirculation

Reply #29 –
I put in a recirculation loop in my water line to the shower. I ran a tee off my hot water line going up the the shower, through a solenoid valve, back to the water fill line to the fresh tank. The solenoid is activated by a momentary switch I mounted on the vanity next to the shower, connected to a timer switch (similar to what Roger linked). When the solenoid is open, hot water is pumped by pressure from the standard water pump through the lines and back into the fresh water tank. I've found that 20 seconds is sufficient to prime the shower line.

This saves probably 40 seconds of running the water in the shower waiting for it to heat up, if you leave the shower mixer valve at its final comfortable warm temperature setting (20 seconds if you turn the mixer full hot). A nice savings if you are boondocking.
I suppose if you were in some really cold setting you could do this periodically for a few minutes to elevate the temperature of the fresh tank and wet bay by a few degrees by cycling the full content of the water heater (in our 295).
Bruce & Linda
2004 U295, Build # 6268, ISL400 CAPS
2016 Ford Explorer Sport or 1985 Jeep CJ7

Re: Hot Water Recirculation

Reply #30 –
Yeah I did something similar going from the Mana block back to my direct fill tank fitting. And I put in everything I needed but I still haven't wired to darn thing yet. I did use a lot of Rogers ideas so thanks for that Roger. I'm really good at doing things on the coach but sometimes not so great at the finishing part. but I'm going to wire it to my old fill switch when I redo my wet Bay once again. since my electric dump valves have seem to crap out and I'm going to go and put manual ones back in it was an experiment and it didn't last as long as I thought it would. I also noticed that waste Master no longer sells the electric valves so they must have been having problems with them that's about $300 I wasted for nothing. Could have bought a lot of beer for for that amount..
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Hot Water Recirculation

Reply #31 –
I'm gearing up to do this project soon. Quesiton: why use a timer relay and not a latching switch to activate the solenoid? Seems like added complexity that results in less control.

As always, thanks for blazing the way for us new guys  ^.^d
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Hot Water Recirculation

Reply #32 –
Quote from: Elliott –
I'm gearing up to do this project soon. Quesiton: why use a timer relay and not a latching switch to activate the solenoid? Seems like added complexity that results in less control.
As I've been thinking about adding one too, I think the idea is to push once and forget it.  With a latching relay, you'd have to remember to turn it off at a certain point as not to recirc your entire fresh supply through the water heater.
Keith
2003 U320 38' #6197

Re: Hot Water Recirculation

Reply #33 –
I used an adjustable timer so that a single press of a momentary switch starts and ends the process.  20 seconds most of the time is about long enough. I can see what happens on the temperature displays. In cold weather we might run it twice.

You don't need a timer, it is an added convenience.  If your water pump is powered through a latching relay that is triggered by a momentary ground (that is what pushing the water pump switch does) an extra pair of Bosch style relays can turn on the water pump when you press the recirculate button if it is not already on.  If the pump is on it does nothing.

Your water pump latching relay can also be on a timer so that it shuts off after a period of time you select so that the risk of leaving the pump on (especially if you are away) is zero.

If you are using a city water connection a 12v ball valve can be added to your incoming water supply.  If you turn on the pump switch, it opens the valve. If the water pump is on a timer your city water connection also automatically shuts off if you are not using water. Risk reduction.

If you are on a city water connection you need to watch your fresh water tank level since you are not really recirculating water from the tank but adding city water to the system that ends up in the fresh water tank.

All simple stuff to make your water system more efficient and safer.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Hot Water Recirculation

Reply #34 –
I finally checked this one off the list. I went all the way to the back of the shower like Woody. There's approximately 18' of half inch pex between the manibloc and shower head which equates to .18 gallons per shower. Not a meaningful amount unless you boondock a lot (which we do).

I opted for a latching switch for simplicity, which I installed under the sink near the water pump switch. When I have more time I'll add a temp gauge like Roger did.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Hot Water Recirculation

Reply #35 –
I really like being able to add hot water to the tank to add heat if it was ever needed. Very nice 👍👍
Scott

Re: Hot Water Recirculation

Reply #36 –
Elliott did you add the spin weld fitting on your fresh water tank and did you use the 3M adhesive that Roger recommended or did you actually spin weld it to your tank?
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: Hot Water Recirculation

Reply #37 –
Quote from: Geodmann –
Elliott did you add the spin weld fitting on your fresh water tank and did you use the 3M adhesive that Roger recommended or did you actually spin weld it to your tank?
I used the 3M adhesive he recommended. The spin welding drill attachment was stupid expensive.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Hot Water Recirculation

Reply #38 –
I put a quick fill on our water tank years ago. Cheap, easy, fast and no leaks.

I use it for a filtered fill but it can be used for anything.

Photos are worth any explanation. uniseal fitting water at DuckDuckGo

https://www.youtube.com/watch?v=Vv14eNJmUeU

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Hot Water Recirculation

Reply #39 –
Interesting. Pierce, did you have to remove the water tank in order to poke the hole in it? The video shows a small tank, already out, sitting on a nice workbench. Not quite real world for me.

Re: Hot Water Recirculation

Reply #40 –
David,

If you have the drill with hole saw ready to go, you can make the hole and install the Uniseal in less than one minute. I was careful not to drop the plastic remaining in the hole saw into the tank. Then, it depends on what kind of fitting you want to push into the Uniseal.

Best to use a felt marker pen to mark where you want to drill the hole, use a small bit to make a pilot hole and then use the hole saw I have included to make the hole. Only takes a second to clean up any plastic debris and then just push the fitting in place.

Here are all the tools I used. This is a 1 out of 1 to 10 in difficulty. I installed the filter housing steel mount on the wall so the pipe into the tank would not move. Probably a good thing to do before you drill the hole in the tank so you can see exactly where the pipe will hit the tank. So, mount the filer bracket, push a plastic pipe into the filter mount and see where it's going to touch the tank and then make the hole. This way, the pipe is perpendicular to the surface of the tank.

No sealer on the Uniseal, just pipe compound on the threads into the filter body. Never even a drop of water anywhere.

The tank fills much faster than the OEM filler but depends on pressure. We drive with the tank low because of all the grades in the Sierras. Once in a campground, I connect and start filling, staying to watch so it does not overflow. Last week, it filled in about 7 minutes as we had good pressure.

No stupid questions, please ask.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Hot Water Recirculation

Reply #41 –
Pierce, nice tip there with those uniseals! Both hot water recirculation and a top fill are on my list of "to-do's" this year.

Two questions:
What size uniseal and PVC fitting did you use on that top fill/filter assembly?

Any tips on how to minimize plastic chips from getting into the tank as you use the hole saw to cut the opening?

Thanks again!  Jeff
Jeff & Kristen
2002 U320 build #6039
Living the Dream!
 

Re: Hot Water Recirculation

Reply #42 –
Jeff,

It was on the photo but our Forum changed the letters for some reason.

I used a 1  3/4" hole saw and a 1" Uniseal. The 1" size is the I.D. for the size of the pipe that slides in. Since I did this a while ago, check the directions when you get the Uniseal.

I drilled the pilot hole pulling the bit out and cleaning it every couple of seconds. With the hole saw, I also went in a few thousands, cleaned the area and repeated it until it went though. The plastic tank is safe but I didn't want any shavings to clog anything but the undersink filter would catch anything in the drinking water and the sink and shower have never shown anything.

I think I used a small piece of coarse wet or dry on one finger to smooth the edges on the tank before I installed the Uniseal.

You could put a cap on the PVC with a tiny bit of paint to mark the center. Then push it in until it makes contact with the tank and then drill the pilot hole there. Or, a tiny bit of paint all around the PVC spinning it a turn or two when it makes contact and then marking the middle.

My pleasure!

Pierce



Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)