Solar Powered RV Water Heater Conversion - 12 Volt Dump Load - Everlanders see the World!

in this video we make a big dump load [Music] so what is a dump load as many of you know we have a ludicrous amount of solar panels and even down here in southern mexico in december and january we have more solar power production than we're using and even though i spend some of that solar energy on our air compressors which power up or air up our air tanks as stored energy that way and we can run our air conditioner as much as we want we still have more solar than we're using and as you can see in this graph the yellow line is our total solar production and it's turning off because the uh the batteries are full there's no need for excess charge so the charge controller cuts the cuts the solar panels and we're not charging anymore and so i'm going to build a solar powered water heater that will act as a dump load and give us convenient hot water all the time so when we were planning our build we considered using our engine heat engine coolant heat or our sbar d5 engine coolant heater through a valve manifold system and preheat the water or heat the water through a plate exchange or heat exchanger system that never ended up happening there are also some nice portable marine water heaters whale makes one that comes to mind and isotherm make heat exchangers that have your coolant lines running through the water volume to transfer heat that way and some are also electric uh but those get a little expensive and we never really justify the cost and now we're in mexico and so we're making do with what i got all right so this as many of you might remember is our shower keg except it's all wrapped up in this shiny silver jacket i did some testing with this where i took my spare battery heater mat it's a silicone heater mat you'll see here shortly and i strapped it to the side of the stainless steel keg wrapped it in this spare reflectix we had along and did some testing and i can try charge heat up our water uh within about hour and a half two hours depending how hot i want it and so that was our proof of concept that this plan you're about to see is going to work just fine so without any delay let me tear this apart uh but that was a lid i made a lid to keep the top bit cool uh warm rather keep the warm in when it cooled out and uh now let's open our up and i'll show you how i built it okay so here is the ds-1820 dallas semiconductor temperature sensor with a headphone jack connector and the silicone mat which has sort of stuck itself to the keg so that's it there that gives a couple hundred watts of heat at 12 volts and it's got a rtc style temperature sensor inbuilt but we won't be using that and here's my keg back to normal again so just in the traveling around we've been doing in mexico we find a lot of these really small cute water heaters underneath the kitchen sink or the the washroom sink and that's a point of use water heater they're a lot more common here than in homes in canada in the us where you have a large 50 gallon water heater or so so i started looking into it and found this little unit happen to be at the home depot 20 off and yeah it's got all the right fittings we need to make a proper water heater rather than keg fittings a drain valve it's kind of insulated and it's 120 volts so i can run it directly off our inverter if i wanted to or off of a grid if i have access to that but i'm going to convert this and make it 12 volt now i know how much all of our viewers like watching unboxing videos so we're going to make this one as quick as possible this is it here it's a wicked tiny super small and light i'm really happy with the size and it's got the npt water fittings right there already and a pressure relief valve now this one happens to be the new and improved double i think it's only double or even triple the pressure of the ones in canada and the us which is really great because if you've ever struggled with premature relief this will solve that for you all right so like i said this is a very small water heater i've never seen one so small in canada or the us um this is made by cream i'm not sure even if i'm pronouncing that correctly uh and although the stampings for relief valve and and hot and cold under these stickers are in english i can find no documentation on it in english all the manuals and and serial number or part numbers rather are all in spanish so i don't know if they are available but like i said this will be perfect little thermal battery for our excess of solar storage so first thing to do with a water heater like this is to test i mean tear it all to pieces this is not the way in there we go all right so there is the original 110 volt water heater element this one is stamped 1440 watts i am aware they do make 12 volt water heater elements like this uh 400 600 and 800 watt variations but i could not find one that they would ship to mexico at this time so i can always do this upgrade later if we find we never use 110 and we want the option to heater up faster i can get a 12 volt version of this water heater element shown here and we might switch that in later but for now we're leaving at 110. that's the breaker built-in breaker and the uh thermostat with selectable between 66 celsius and 32 celsius it just interrupts the circuit and hopefully this just slides out of here now this little bit of rock wool a little bit of masking tape just they've just folded it over and jammed her in nice perfect looks like a world war ii bomb coincidentally that's part of the reason i didn't like our shower keg apparatus is it looked like some janky homemade looking thing and going through a military check stop i'm sure i would get some raised eyebrows with that so now all there is to do is uh put this back together with the heater mat on it all right so i want to put the heater mat right here but there's lots of welding splatter actually very big welding splatter chunks on here so i'm just going to take a flap disc and smooth these out [Applause] all right so they just used basking tape on the inside of this thing to put it together so i'm going to do the same just enough to hold it in there while i stuff it back in the case and i have this janky old roll i've been dragging around from canada twice all right got that on there just needs to hold long enough to get to get the cover back on and then the ds 1820 everyone's favorite one-wire sensor i'm going to put offset from that just a little bit so that it doesn't pick up the heat of the mat so much as the heat of the tank yep gonna stay away from that all right got that mostly put together uh like i said this silicone mat has this ntc temperature sensor built into it but i've never used it and it's always in the way so i'm going to at least trim it shorter to help put this thing back together sweating out of my titties here all right so there's that part all done up uh now i need to find me a place to route these wires out of the enclosure and to do that i'm gonna drill a big hole in here all right so i've got this little rubber grommet i've been carrying around for a while space that up from the bottom put the hole there many thanks to our campground friend stefan who lent me a step drill that could have been the end of the table nice this little unit just pops in there so classy all right now i get this whole thing back together must complement the manufacture of this fine product on the use of paint and paint accessories to put this thing together beauty like it was factory all right now to shoehorn this thing back in there whoops this must have been the bottom so professional then pop on the [Applause] cover might need a bigger hammer or more lube nope we got here not bad the bottom cover which hopefully isn't keyed thermostat back in i can hardly tell anyone is even in there except for this all right so we just had a little lunch break there had a nice salad and now we need to cut up some copper pipe just to join these brass and copper fittings together i need to solder this uh l bracket in there just to make room some nice clearance under there and then thread these in and i'd like to take this opportunity to thank all of our supporting channel members i know it's been a few weeks since we've put out a video for you guys but we've been camped out here with giants of over landing several big expedition trucks from europe have rolled in from germany switzerland and holland so we've had a really great time with them made a turkey supper for christmas several of those people haven't had turkey before so that was kind of neat to share with them and yeah so had a really great time with them but time to get back making some videos here so got these fittings all in now it's time to head in and install it alright so to install this water heater the best place for us is going to be as close to the kitchen faucet as possible that way we need to waste less water as the as the lines warm up and it gets warmer so underneath here is going to be the best place for us also it's nice and small and convenient size so it fits in there pretty good all right so under our sink we have right now just soap and and kitchen trash and that sort of stuff and there is a false bottom in this cupboard which holds our freezer compressor as well as the espar d2 heater so just give me 10 seconds i'm going to pull this apart and show you guys the nitty gritty of it so lots of room in here to work with let me bring you in for a closer look and we'll give you the rundown of the plan all right so these are our water filters for our drinking water uh long time viewers might remember we originally installed them under the dinette floor over here but when we installed our lithium battery bank upgrade they moved to the side compartment door and they worked fine there because they were close to the water kegs but it was certainly far from ideal it was a waste of space just the way it was installed and so stefan helped me move these up in here so this lives now behind our sink basin where our sink basin sits and utilizes this space that was previously wasted and here on where the false floor is covering our freezer compressor and our sbar d2 i've cut out a hole with the help of stefan in this false floor so that we can drop the water heater down another two inches approximately and then it will be sitting right here on this wheel well and then i've made this little bracket strap assembly i 3d printed the cradle shape there and then installed some adhesive-backed foam strip and then glued this piece of webbing strap to it and then pre-drilled some holes here for the to to line it up so that it's lined up nicely and now i'm ready to install it [Music] and as you can see here i've got some 10 gauge cable which is twice as thick as the cable on the heater mat but it'll be good soldered up to a xt60 connector and that's sitting here ready and waiting and then also a connection for the ds-1820 right here and so the little cutie water heater goes there like this cinch down on this strap like this and there it is nice and solid i've just wound up the 110 outlet because i don't think we'll be using that for the time being all right and then next i need the connection for the sink so this goes back in screwing up cara's shot you can see there our fancy endless soap supply and then next we hook up the hot side of the faucet to the outlet side of the motor heater that connection has a rubber connector uh o-ring in there so it doesn't need the teflon tape and we just connect our very conveniently located xt60 power connector and the temperature sensors here somewhere here's the connector for this i need to tie this all the way nicely here in a bit and of course i need to add the water incoming water so let's do that now this plastic fitting here is temporary i have a brass one on the way that's proper 3 8 so i don't want to cut this tubing because it's only here for a couple weeks so this is not permanent but that goes to there and then i fit that to there and that to there temporarily and then pressurizing the water keg with any luck it should fill with water and not leak everywhere [Music] all right guys it's been a couple days since i wrapped it up as wrapped as it's going to get anyway as you can see up here at the top i've got a led light strip which kind of lights up the interior of this cabinet nicely i originally did that solely for this video just temporarily but i liked it so much that i thought i'd brighten up this typically dingy spot so that's pretty cool the water filters are tucked up here behind the sink basin utilizing that previously wasted space the ballast for our uv sterilizer which you can see here it puts out a kind of a weird eerie glow through the fittings as you can see and then the star of the show the water heater socketed into this floor here that hides our uh fridge freezer compressor as well as our espar d2 heater you can see the vent for it here i did check with a thermal gun the outside doesn't get too much hotter than ambient thankfully except for the copper fittings are a few degrees warmer on the top the copper and the blow-off valve so i'm going to insulate those here in a little bit that's it for here for now now let's check out the control system and how i'm controlling this using our excess solar all right so in our electrical control bay now these are our p-channel driver boards that i built in another video i showed you how to do that you can click in this card up here to see that or as they've been come to known in the campground todd boards and there's not much to this just the wire this is the 10 gauge cable coming from the water heater that comes up into our high current driver board where it is controlled by this raspberry pi which is monitoring the ds 1820s temperature and when the criteria are correct it flips on this high current driver heating the water so let's jump up into the computer now and i'll show you that all right next of course is the control system control loop that monitors the temperature and diverts our excess solar to the water heater element so this is very early in this script development i will be posting updates to this to our website everlanders.com as things develop but i'll just give you a quick overview and then we'll we'll just give you a quick tour so so this is the script and i'm gonna really skim over it quickly here uh these first parts import external libraries boring uh this is the stuff it sets the warnings to false water heaters on pin one which i'm using the bcm pin numberings which converts to pin d3 on my heavy duty driver board and sets it to an output then i declare the low voltage cut off at eighty percent of our our system voltage uh the set point is passed in as a variable the set point is basically the temperature that the water heater is shooting to maintain and the device file is simply the ds 1820s path where it stores the temperature for that particular unit these two parts here whoops these two parts here are functions that call that file and convert all the gerbrito into english metric english and celsius and then this is the main logic right here uh if the state of charge is greater than the low voltage cut off then uh read the temperature and if the temperature is less than the set point i.e if the temperature in the tank is less than what i've set it to which is 60 then print turn the heater on and turn the output for the water heater on else if the temperature is less rather greater than the set point if it's as hot as it needs to be turn the heater off really really basic and then this block down here is basically if this top block is not true so if the state of charge is less than the low voltage cutoff then the batteries are too low below the 80 threshold and declare batteries are too low switch the heater off and print out the temperature for fun okay so then let me just show you how these are being called let's jump in here again they're being called by the crown tab very basically so it's the second line here it runs every minute and checks if the temperature is below the set point and if the battery level is above the safe threshold and if so turns it on and sets the target temperature to 60 degrees so i just come in here and change this as i need to to make whatever adjustments i need and then i have this first script running as a fail safe force water heater off and that runs every 30 minutes and the reason for that is uh if the one wire bus crashes or if one of the sensors fails it takes down the whole bus so all 10 of my sensors would go offline if any one failed and if the water heater happened to be on during that time it would go into thermal runaway and stay on until the pressure relief valve relieved so don't want that to happen so every 30 minutes it turns off it only climbs you know 20 degrees in 30 minutes so okay guys the last thing i wanted to show you was the water heater temperature graph as shown in blank so i'll put that on screen now unfortunately i did unplug a sensor and then plug it back in which has caused this this missing data here and then this erroneous spike to 85 celsius but as you can see uh overnight this is 4 am the temperature in the tank goes down because i have it switched off and once we hit 8 o'clock here the temperature starts going up you can see in the top right there 59 degrees and then even though it's maintained the temperature all day today and i have the set point set to 60 and so it just toggles between 59.5 and 60 degrees celsius and through the course of the day you can see the green line above that that's our battery state of charge and we're still fully charged today and then there's two other little things i wanted to point out here these two dips right here these are uh where i washed some dishes at 127 and 153 i took a bunch of water out to start a sous-vide cook so i started with pre-hot preheated water just to to save the save the energy from the sous-vide running directly off the solar and so but the point i wanted to show is now you can see the water temperature recovering from 58 to 60 in pretty short order so we've been having this running in some state or another for the last week or so and it's been really nice to have on-demand hot water with power that would have gone to waste so all right guys that's going to be it for this one hope you guys found it interesting i do have a new idea and that is to have you guys vote on what you want to see next since this video will be going to our channel members uh a week or so before everyone else it will be weighted towards what the members want to see but i will consider non-members votes and and opinions if there's a landslide that way uh so here are the list of things that i'm working towards uh making videos on let's see what you guys think number one is build a 3d printer into the truck and convert it to run directly off of solar and that way i'll be able to make some parts and help people along the way i've already actually got the printer here but i need to do a bunch of modifications to modify it to suit our needs but it has been it's proven invaluable already making all sorts of brackets and and fittings for other people on their rigs so that's something i'm working on the next item is a max fan retrofit repair extravaganza i know the max fan deluxe is one of the more popular fans out there we see them every day and every day we hear about people's complaints of the motors being squeaky or problems with the circuit design where it will shut off at 14 volts which is everybody's lithium battery bank and and the brush is wearing out in fact this fan above my head here after about two and a half years we've worn clean through the copper commutators in the motor and so i'm going to try and field repair that on the side of the road here so that's another option uh lora communicators is the next these are laura esp32 boards come on you focus about 25 or 30 bucks comes with a battery connector esp32 lora long long-range radio and a gps receiver and a little screen and i've got a handful of these and i want to make a little mesh network among travelers and we can send messages to each other when we're in areas of off-gridness here's one that i whipped up that uses a 3d printed case come on you shank it happen it's a surprise the next thing is dc to dc conversion so many of the products we use at home are uh 110 voltage plug-in items and then there's a power brick and it converts it to something else this laptop for example uh has a 300 watt 19 volt power adapter and our dyson vacuum is also 19 volts but much smaller current and so on and the 3d printer also uh 24 volts so we'll see if converting from just dc to dc gains us much efficiency over dc to ac to dc to different dc so there's always going to be some losses in the conversion so that's something that's interested me for a while so i'm going to give that a go so let me know what you think i'll see if i can put a poll link up in the top corner there check that out or failing that just leave your comments down below what you think you want to see let me know what you thought of this video i know some of my projects are a little bit fringe and may not appeal to the masses but hopefully you found it at least entertaining all right so thank you all for watching especially our supporting channel members if you guys are interested in watching these videos without advertisements and a week or so early check out the join button down below and uh thank you for watching we'll see you next time you

Channel: Everlanders

Views: 94,991

Keywords: Solar Dump Load, Solar water heater, RV Solar Water Heater, Off Grid Water Heater, 12 volt water heater, solar water heating, solar powered water heater, solar panels for rv, off grid solar power system camper, off grid solar, solar panels for van, off grid solar power system rv, Overland Solar, Overland Water Heater, Overland Christmas, overland build, Overland Couple, Vanlife Water Heater, Everlanders Solar, DIY Solar Water Heater

Id: _u0URusLxnk

Length: 30min 51sec (1851 seconds)

Published: Tue Jan 12 2021