i am surprised the plastic water cooler does not melt.

i once drained 5 gallons of 175 degree motor oil into a 5 gallon plastic bucket, it melted the bucket not long after it was full, it was quite a mess to clean up. live and learn.

 

Since I don't generally take a 175º shower, it's not a problem. I'm good at around 100º.

 

Bicyclists , what do you do when the weather is below freezing?

 

Stay home.

 

I like it. Good location for the Eccotemp. Why not just take your showers straight off the Eccotemp and skip the water cooler tank?

 

I turn the water on and off to conserve. Ya get a short blast of really hot water when you turn it back on if you shower straight off the Eccotemp. But the tank also lets me heat water electrically.

 

Great ideas !
Leave room for expansion and pressure build up.

 

I was wondering why people do not use the solar heating idea for water.

My parents, and many others, had solar panels on the roof of their house with a circulating pump to heat their pools. We had to limit the solar to a few hours after the end of May or the pool (good sized) would be to hot to swim in.

So with a small solar water panels mounted on the roof, or portable, why aren't people using this idea instead of all the contraptions for electric heat or propane?

 

I was wondering why people do not use the solar heating idea for water.

Quite a few threads about the "water bags" you can hang by the back door and heat up in 15 to 45 minutes.

Simple solution, but a 50F cloudy day is still great for hiking/bike riding, but those bags don't get hot enough!

Worst is getting back to camp as the sun goes down! I like the heater in the water bucket idea so that I could shower on 100F day. Quick rinse/lather/rinse in hot water before calling it a night is good!

All great idea's, keep them coming!

 

I have a Big Kahuna 8 gallon shower. I've gotten use to boiling up some stream/river/lake water and mixing it with the ambient temp water already in the 8 gallon container. Not a hot shower, but better than a cold one. This is the best solution for my boondock adventure van build, need to save water, and because I wanted as few moving parts as possible to avoid failures. But the Ecotemp heaters are an easy system, just not conservative on water.

 

Using an insulated cooler is a good solution for creating a hot water tank. Just set up the water system so it goes through the heater and circulates BACK into the cooler/tank for a while before you turn the valve and have it come out for a shower. Water mixing, cold/hot, so you get the temp you want would be nice, or you can have a thermometer in the cooler/tank and when it is at your preferred temp (100) THEN turn the valve and take a shower directly from the tank. This way you also don't waste water waiting or testing it until it's the right temp.

 

In sold Sprinter I had a free 5 gallon SS beer keg. Bought a RV propane to electric heater conversion kit for about $80. Kit has 120 volt AC electric heating element and a thermostat. Welded a coupling on tank bottom for the heating element and attached the thermostat to the tank. Removed the internal keg tube and dropped in a 12 volt DC cylindrical pump. Use garden hose and nozzle. Used vehicle powered inverter or shore for heating element. Took about 45 minutes to heat the water to 90 degrees.

A couple of improvements for the Transit. Had a 6 gallon 14 ga. SS tank welded up that uses the wasted space under the portapotti and supports the portapotti at the correct height. Changed vehicle powered inverter from 600 watts to 1000 watts which allowed me to buy a 625 watt heating element instead of the Sprinter 450 watt element. A selector switch is used to select 120 volt power from shore, vehicle inverter of from house battery/inverter when I have excess solar power. All the water in the tank is at shower temperature so no plumbing or hot/cold mixing required. Higher wattage heating element should reduce water heating time down to about 30 minutes.

Same method could be used with a 12 volt heating element to reduce the cost.

 

Bucket Heater

[ame]https://www.amazon.com/Precision-Premier-Line-742G-Submersible/dp/B000BDB4UG/[/ame]

 

FWIW, as I posted in another thread, I simply purchased a electric water heater with a heat exchanger and use the engine coolant heat to warm water. I didn't bother hooking up the electric. Of course it only works during driving, but it avoids having to wire a huge gauge wire to drive a heating element. I also use the Ecotemp for dry-camping.

The water heater comes with a 120 volt heating element, but I bought a 12volt one, and now I'm not using either. If I even get a big inverter, I might reconsider, but the heat exchanger is working so well that I'm not sure I have the need. Also, the advantage is that it's a steel tank that already has the fitting for the heating element. Will post a build thread soon elsewhere.

 

Attached is a PDF I found online from 2012 that covers how to build a 12 Vdc water heater that runs off of excess current from a Solar Charge Controller. The concept is that once batteries are topped off the panels are still making juice the controller doesn't use and this could as easily be used to heat water instead of heating a resistive load in the controller for that purpose.

I haven't seen anything to indicate that modern charge controllers run their excess energy to resistors, or, that this source could be tapped. But figured it might be worth pondering among those more familiar with the perhapsability of such a design, just in case it is viable.

Edit: Thinking further along these lines it could be done if there were a device that detected the battery reaching a particular voltage and switched the charging circuit to the heating element. I've now read how modern charge controllers will either cut off or pulse width modulate the output to the battery based on the voltage they see, rather than send excess energy to a load resistor. The voltage detecting switch would need to be set a few tenths of a volt below the charger's cutoff point.

To put it another way, the water heater would take voltage from the House battery once a set voltage was reached and break the circuit if the battery voltage went below some set level. Thus making use of all the energy the solar panels are providing.

 

Here's a link to a PDF from 2012 that covers how to build a 12 Vdc water heater that runs off of excess current from a Solar Charge Controller. The concept is that once batteries are topped off the panels are still making juice the controller doesn't use and this could as easily be used to heat water instead of heating a resistive load in the controller for that purpose.

I haven't seen anything to indicate that modern charge controllers run their excess energy to resistors, or, that this source could be tapped. But figured it might be worth pondering among those more familiar with the perhapsability of such a design, just in case it is viable.

Edit: Thinking further along these lines it could be done if there were a device that detected the battery reaching a particular voltage and switched the charging circuit to the heating element. I've now read how modern charge controllers will either cut off or pulse width modulate the output to the battery based on the voltage they see, rather than send excess energy to a load resistor. The voltage detecting switch would need to be set a few tenths of a volt below the charger's cutoff point.

To put it another way, the water heater would take voltage from the House battery once a set voltage was reached and break the circuit if the battery voltage went below some set level. Thus making use of all the energy the solar panels are providing.

a solar dump load controller (Morningstar Tristar) but that opens a whole new can of worms, the Tristar is an PWM solar controller Not a MPPT solar controller.

https://www.morningstarcorp.com/products/tristar/

(your link by the way does not work.)

 

Am thinking seriously about the solar dump load and alternator dump to heat my water tank (35 gals.)in the winter. I have a propane on demand water heater. So preheated water would make it more efficient. Also heating the water would also help warm the air also.

 

Heating shower water does not need to be complicated.

I can heat shower water using three separate 120 volt AC power sources. The water tank has a thermostat that turns the heating element on/off depending on the tank water temperature. The choices are selected manually. The shower water is in an uninsulated 6 gallon SS tank. Design is not used to maintain warm water in the tank continuously. Operate the system only when you want to take a shower.

The first source is shore power if available. A selector switch is used to select shore power. The Transit engine does not need to run.

The second choice is power from the vehicle powered inverter. The same selector switch is used to select this source. The engine needs to be running to heat water using the vehicle powered inverter. Do not want to deplete the vehicle battery heating water.

The third choice is using the house battery/inverter to provide the 120 volt power for the water heater. Water can be heated without the engine running. This source can only be used if the weather conditions allow depleting the house battery. Must pay attention to determine that solar will be able to recharge the house battery that day. The solar panel and MPPT controller are independent from the water heating. If I heat water using the house battery the solar controller will replenish the house battery.

The selector switch selects either shore power or power from the vehicle powered inverter. The heating element is powered with a 3 prong plug. There are two duplex outlets mounted next to each other. One is powered by shore power and the other is powered by the house battery/inverter. I manually plug into the source I want. Once water is heated I unplug the power cord to the heater before showering.

Do not directly power water heater from the solar controller. Solar controller reacts to a depleted house battery charge level to recharge the house battery. The value of a MPPT solar controller is its ability to input high voltage & low amperage solar panel power to output lower charging voltage & higher amperage to the house battery. In my case my 32 volt panel voltage is reduced down to the charging voltage. The formula is input voltage x input amperage = output voltage x output amperage. With a high voltage panel the charging amperage is much higher than a PMW controller would provide.

 

Heating shower water does not need to be complicated.

I can heat shower water using three separate 120 volt AC power sources. The water tank has a thermostat that turns the heating element on/off depending on the tank water temperature. The choices are selected manually. The shower water is in an uninsulated 6 gallon SS tank. Design is not used to maintain warm water in the tank continuously. Operate the system only when you want to take a shower.

I want:

• to maintain warm water in the tank from essentially free sources that are available on the van.
• water to already be at least warm when I turn on the tap.
• the system to operate pretty much automatically, with near zero impact on the House system.
• excess Solar energy that would otherwise be left on the table to be used to take up the slack by heating water when it is available.
• the vehicle to heat water whenever I'm driving the van.
• to be less dependent upon shore power or having to idle the vehicle to make hot water.

Your setup is cool, and I've given that method consideration. The system I've described better meets these goals.

 

Last week I tested the 12 volt DC circuits, and was able to use the water pump to pressurize the plumbing and check for leaks. Yesterday, I finished up the 120 volt AC circuits, so one of the tests was for the heating element in the water heater.

I'm using a Kuuma 6 gallon marine water heater that is located under the bed next to a 25 gallon water tank. Both are just forward of the rear axle for proper weight distribution. With the 120 volt shore power, there was plenty of hot water after a few minutes. The heating element in the water heater draws 11 amps, so if someone wanted to do this with an inverter or generator, you would need to plan accordingly.

One of the reasons I chose the Kuuma marine water heater is because in addition to the electric heating element, it has a double wall heat exchanger that can be connected to the Transit's engine cooling system. The plan is to tap into the van's heater core line, and run additional heater hose to the Kuuma water heater. This will provide a source of hot water just from driving.

http://www.discountmarinesupplies.com/Water_Heaters-Kuuma_120V_Electric_Water_Heaters.html

 

Yes, I already did this. I did it with a 3 gallon model, and I didn't hook up the AC at all, went with the straight heat exchanger circulating coolant from the engine. It heats up the water to very hot (scalding) in 10-15 minutes of engine runtime. It holds that heat for at least a couple hours. Very happy with my setup which is usually used within that time period after driving. I shied away from the AC hookup because I rarely hook up to AC, and because of the current requirements as you correctly point out.