Plausibility of 2 gallon electric hot water heater?
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Living in one of the coldest regions of the continental U.S., solar often falls short of providing water suitable for washing. Being a camper at heart, I don't need a lot of hot water. Laundry is done at my Denver bungalow every two weeks. I like to wash more than every two weeks of course. Having spent 14 months in various casts after a significant climbing fall, washcloth bathing is pretty familiar.
I could not resist an older 2 gallon unused, still in the box, Reliant electric hot water for less than $50. It consumes 1400 watts but is insulated and is a small 2 gallon unit. Convenience lies in simply plugging it in. The heating element carries a lifetime warranty which means nothing at this time other than pointing at a somewhat likely robust heating element.
I plan to gravity feed it from my 200 gallon holding tank. The hardware store plumbing guy sold me two brass 1/2" male to male fittings for the inlet and outlet at $4.50/each. Perhaps possible corrosion issues makes this a wise choice? I already have 1" Spears valves to control water flow. Plus T's and hosing. So hooking it up looks like $9 for the brass fittings...so far.
Experienced off gridder's see a problem with this? Perhaps I should put a timer on the electric plug and only run it during solar hours.......
My unused propane hot water heater is 50 gallons and would consume a lot of propane.
I could not resist an older 2 gallon unused, still in the box, Reliant electric hot water for less than $50. It consumes 1400 watts but is insulated and is a small 2 gallon unit. Convenience lies in simply plugging it in. The heating element carries a lifetime warranty which means nothing at this time other than pointing at a somewhat likely robust heating element.
I plan to gravity feed it from my 200 gallon holding tank. The hardware store plumbing guy sold me two brass 1/2" male to male fittings for the inlet and outlet at $4.50/each. Perhaps possible corrosion issues makes this a wise choice? I already have 1" Spears valves to control water flow. Plus T's and hosing. So hooking it up looks like $9 for the brass fittings...so far.
Experienced off gridder's see a problem with this? Perhaps I should put a timer on the electric plug and only run it during solar hours.......
My unused propane hot water heater is 50 gallons and would consume a lot of propane.
First Bank:16 180 watt Grape Solar with FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
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I am available for custom hardware/firmware development
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
Also, if I recall correctly, you have very cold weather/winters... Ability to drain system/preventing freezing will be important too (not that a guy from sunny California needs to tell you this
And the Brass couplings (and 6" of brass pipe or so) is a good transition from iron pipe (and water heater tanks) to copper systems (if not using a dielectric union).
-Bill
There will be no real system. Just gravity feed from the holding tank...the temperature in the sunroom never drops below 38F that I recall. Warms up nicely during the day since this area is rated as an alpine desert....very sunny.
I am available for custom hardware/firmware development
It has no thermostat setting. It probably runs much hotter than I need for bathing.
I have no real expertise on my Absorb and Float cycles. Having installed the electronics in a cool, dark spot that takes an effort to get to. Some people study their charge controller doing it's work, I do not.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
You could just run a full size water heater, put a timer on this or a full size water heater. I have been running a 3600 240 water heating element off of 120 (at @900 watts) for 5 years. It's worked out okay, Takes perhaps 4-5 hours in the summer when in coming water is warm and 7-8 maybe in the winter when water comes in very cold. You could setup a 'holding tank' inside to preheat the water to inside temps.
I am available for custom hardware/firmware development
People think I have a life of leisure because of good solar and a large "place"....it is actually a shop. They could not be more wrong. I am simply tired of a lot of people and idiotic government. I would rather be poor than graft a higher income from such.
Here is a chart of the rough amount of energy required to increase water by volume of the tank in 1 hour, they show 1.6 Kwh for a 20 degree rise....
http://www.tempco.com/Engineering/wattage_estimation_tables.htm
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Which is why the cold water inlet goes to the bottom of the tank and the hot outlet draws from the top of the tank.
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.
Sometimes dip tubes fail and water heaters seem to have much less hot water capacity because of the broken dip tube.
-Bill
Since I have this little tank, I may as well use it. I can take nice big showers in Denver bungalow.
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.
With regards to Bosch instantaneous water heaters, keep your purchase receipt for warranty claims, the heat exchanges are prone to failure by leakage, the warranty is good, as long as the reciept is available, based on experience, 3 failures in 3 installations, same problem.
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In my case one came with the house,(no receipt), still works, I bought a brand new one for $50.00 from another homeowner in Baja. He installed a new shower valve and tiled the shower, only to find the flow rate of the shower isn't high enough to spin the heaters impeller fast enough to generate spark. I would have removed all water saving features of the shower valves/head. He gave me an extra copper heat exchanger as well, but no receipt as far as I know. I will look through whatever paperwork I may have gotten with it. It has been sitting for over a year now and I don't recall if I ever did get paperwork.
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.
Bad stuff, that Mexican water. Especially the brackish stuff in our campo's well. Its below sea level. Surprisingly it works fine for showers, dish washing and laundry.
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.
Sailors did not often have the luxury of freshwater until pretty recently. I do not recall saltwater R/O systems being viable even 30 years ago. Though their only real difference is running at 800-900psi instead of 40-125 psi. Brackish R/O systems are run at pressures commensurate with the level of salinity of course.
The main problems with seawater are; it promotes corrosion, and the head gets smelly.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.
I am available for custom hardware/firmware development
Since installing our opportunity hybrid system, our propane use is now 100 lbs per 150 days, or about 1/3 lb per day. (Stove and hot water heater now run off of one 100# tank.)
My system consists of the following:
Schneider XW 4548, Schneider MPPT 150-60, 3000 watt array, 16 - US Battery 420 ah L-16's, Atwood 6 gallon LPG water heater (pilot light model), GE 8 gallon 120v (1500w) water heater, 12v activated 120v 1500w ac relay.
The electric water heater feeds the propane heater. I keep the thermostat on the propane heater colder (but still plenty hot) than the non adjustable electric heater. From May thru August 90% of our hot water is solar generated. Thay percentage drops pretty quickly as the days get shorter, but that is included in my averages. One thing to note is that I use the pilot light model Atwood heater. The pilot alone keeps the water hot, in fact hotter than the reduced thermostat setting. I don't know how much propane the the pilot uses, but it can't be much.
The electric heater is controlled by the relay which is controlled by the charge controller. I have it set to turn on the heater when the batteries reach 60 volts (absorb setting) and turn off at 49.9 volts, .1 volts below the recharge setting. I have kept a very watchful eye on the batteries, checking SG regularly and they seem to like this setting. The heater never comes on at night or if is really cloudy but the gas heater takes over seamlessly.
We use between 9 - 12 kwh per day, the variables being automatic dishwasher, laundry, and extra running of the water pump (220 volt submersible) to change the hot tub water (500 gallons). We can manage consumption during cloudy periods, the dishwasher, for example uses 2 kwh between washing and heating water. Some might say that they want or need more hot water capacity, but we find that we have plenty and never run out.
This setup works pretty well for our system and needs. I hate hauling propane all by boat or over the ice in winter. One tank a year now.
Brian
toilets!
Stick with the old style tanks..
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West Chilcotin, BC, Canada
I have six large solar water "heaters"...........4' x 10' I think. I should get off my rear and get at least one working. Made in the 80's......good chance they would still work I think. Unless the interior copper piping ruptured....which is always possible.