Homemade Solar Water Heater Forced Circulation With Mini Pump




This is a project on a homemade solar water heater.
There is not a project for entertaining, has three years of use on my roof for 4 people shower and dishwasher.
260Liters water is in summer about 60-70ºC
260Liters water is in winter about 30-40ºC, my system able for reduce capacity and work with less liters.
Combination of elements planned than i used give me a result really surprising.

My system has the following advantages.
- My water bottle:
Its of plastic for food, is hot water resistant.
As plastic does not rust and does not produce lime.
Pressure is open, has a small vent tube that releases any pressure to the drum with reduce temperature, filling a floating buoy to fill with open pressure, and water fisherman pipe to collect hotter upper level.
Very good insulated with aluminum paper, polystyrene, polyurethane and cardboard.

This system is great because commercial systems always mixed with cold water while the hot water is consumed.
My system allows me close cold water on cloudy days, and botle gives me all the hot water without mixtures.

- Screen plates:
The plates are copper tubes, aluminum foil absorber domestic economic and readily available, insulate with polystyrene, polyurethane and aluminum paper,
The display with double layer polycarbonate. (not glass, glass is not good insulator of heat and is delicate to handle and easy to break)

- Circulation system:
A circulation system easy to install and very smart to get to the last degree heat.
This sistems is one differencial thermal electronic, a hot water pump brushless.

My full project is in two languages.
English: Homemade Solar Water Heater forced circulation with mini pump -> en.misolarcasero.com
Spanish: Calentador Solar de Agua Casero de circulación forzada. -> misolarcasero.com

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    13 Discussions


    Question 10 months ago

    I would like to know more about where you got the pump and controller.


    2 years ago

    does it metter what paint to use?


    4 years ago on Introduction

    Nice solar hydronic system. I went the path of solar air heating. Maybe one day I will merge the design principles in my heater along with what you did. Pretty cool man! Here is my setup. Also, you notice I have a wood-fired hot water system - ever think of going that route in addition to solar? like running a copper coil through your existing system and ALSO through a wood-fired boiler for when you have no sun! Kind of like i have no damn sun in my region this year that much? Thanks man!

    2 replies

    Reply 4 years ago on Introduction

    It's very interesting your page.
    It is true that if you do not get much sun is not profitable to spend a lot of money to use it.
    My project is like yours the air, but to heat water.
    In my country, Spain, the sun is abundant, and companies that install these devices charge a lot of money, some companies do not have the necessary experience and are the incidents and breakdowns nonstop.
    Your project firewood is also popular.
    The most important thing is that you know adapt to your region and make ambitious projects and intelligence, to save some money and not be a consumer more expensive products and greedy market.


    6 years ago on Introduction

    Forgive my ignorance, I never built one of these. But is it necessary to force circulation, convection being a so effective force?

    7 replies

    Reply 4 years ago on Introduction

    i'm sorry, i never felt i have messages here
    Not need it, just for improbe powerfull of system, comparing with natural circulation is very best effective forcing circulation.
    Why? natural circulation work with differential pressure, heat water is high pressure and viceversa, but, for this action it need it much differential, result is not circulating when panels is not very hot.
    In other words, natural circulation starts when much difference between panel and water deposit, and stop when still hot water in panel

    With forced circulation you can do for start circulation to 5º of difference or less, and stop when difference is 3º

    i'm sorry my bad english, i'm spanish
    Thanks for your comment


    Reply 4 years ago on Introduction

    Apache, entiendo tus argumentos pero no los comparto. La circulación forzada consume energía y agrega un elemento más de complicación y posible falla al sistema. Además, si la diferencia de temperatura es de menos de 5°, sean estos Celcius o Fahrenheit, lo mejor es dejar que la naturaleza siga su curso en paz. Es mi humilde opinión.


    Reply 4 years ago on Introduction

    Hombre, si quieres aliarte con la naturaleza duchate en la calle con agua fría jejejejeje... Es broma.
    No se la diferencia que necesita los sistemas de circulación natural, pero si es de 25 o 30º Celsius, imagínate la de veces que no se pone ni en marcha.
    No intento que compartas mi opinión, pero piensa que la electrónica es nuestra revolución, y se usa para sacar provecho a las cosas, para todo, no es que pretenda reemplazar lo natural con lo artificial, pero lo aplico como un complemente, para potenciar lo natural.
    La electrónica y su gasto, a veces va en linea a lo ecológico, aunque no lo parezca, por ejemplo, los coches que ya no usan carburador y ahora usa un ordenador dentro que controla en tiempo real la mezcla de combustible y oxígeno han hecho que los coches sean mucho más potente gastando mucho menos.
    En este caso, lo que hacemos con la electrónica, que además es de muy bajo consumo, es potenciar la fuerza del sol, cada caso y cada circunstancia puede ser una u otra cosa, pero si vives en una gran ciudad donde la electricidad está asegurada, el gasto de menos de 10Watts a la hora para hacer posible no encender un calentador de gas, ya está más que justificado ¿no crees que eso también es ecológico?
    Si por no gastar electricidad de una pequeña bomba me vas a gastar gas, o encender una resistencia eléctrica, ¿donde está lo ecológico y razonable? o es que nos vamos a esperar a primavera para ducharnos de forma ecológica? jejejejeje
    En cuanto a la complejidad, mi proyecto es de presión abierta, te ahorras la seguridad necesaria para aguantar altas presiones, te ahorras el diafragma para amortiguar golpes y excesos de presiones, válvula de seguiridad, y si encima usas un depósito de plástico(posible gracias a la presión abierta), te ahorrarás también comprar un depósito cada 5 o 6 años.
    Gracias por tu opinión, yo te razono mi parte, y tu decides si aportar algo más, la diferencia de opiniones puede ser algo muy constructivo.


    Reply 5 years ago on Introduction

    I would say it's not necessary. however in this setup, the flow direction is changed very abruptly in both top and bottom connections, reducing the effectiveness of convection currents