Solar Hot Water Heater from 2007

[SolarRich]

Like others here have done, I wanted to share my solar hot water heater I installed in 2007. There's 4 zones(domestic hot water Tank1, domestic hot water Tank2, House, Garage), each with a standard zone valve. And 2 pumps. One pump for the house, tank1 and tank2 and one pump for the garage.
A custom made arduino based controller runs it.
Each tank is a standard off the shelf 'indirect fired' 60 gallon stainless steel tank with built in heat exchanger. These were made to be used as a zone off a gas or oil fired boiler. Non toxic antifreeze is used in the hot loop to the evacuated glass tube collectors and then to each zone.
The controller brings the tanks up to temp first. Then the house gets heated or the garage depending on season and needs. The controller is hooked into the house thermostat so they talk to each other.
To heat the house a standard hot water radiator was used in the air handler.
To heat the garage the antifreeze is pumped thru pex tubing in the insulated concrete slab. Although rarely is there enough energy to heat the garage as it's last on the priority list. The garage is the dump load during the non-heating summer months.
This thing has worked flawlessly for 15 years. Those evacuated glass tubes work very well in the winter.

 

[OzSolar]

Thanks for sharing. I always wanted to play around with evacuated tubes and space heating but never got a serious chance. I did have the misfortune to be called to dismantle a fair amount of Carter tax credit era flat plate space heating installations that failed for one reason or the other.

 

[Mart Hale]

I have been using a solar tube to cook with for some time.

Rand Solar vacuum cooker Modifications of Stand, end cap, Temp probe

Rand Solar vacuum tube cooker modifications

odysee.com

I have been watching what others do with these, one guy fills it with sand, then heats the sand, then poors the heated sand into a cooker then cooks on top of that heated sand like a thermal cooker. I am looking to build a hot water heater via solar in the design of Desert Sun has done...

I was thinking of building a chamber out of aircrete mixed with styrofoam, then in this chamber store sand with a pex pipe layed in the sand. Then I would use solar, or a rocket stove to heat the sand via the pex, then to pull the heat off the chamber I would use either the same pex or another pipe running thru the chamber via heat exchanger for like a shower..... I am still in the design stage in my brain, I have the pex, but I am waiting on finding a window to move forward with the design.

 

[carl2591]

I have been using a solar tube to cook with for some time.

Rand Solar vacuum cooker Modifications of Stand, end cap, Temp probe

Rand Solar vacuum tube cooker modifications

odysee.com

I have been watching what others do with these, one guy fills it with sand, then heats the sand, then poors the heated sand into a cooker then cooks on top of that heated sand like a thermal cooker. I am looking to build a hot water heater via solar in the design of Desert Sun has done...

I was thinking of building a chamber out of aircrete mixed with styrofoam, then in this chamber store sand with a pex pipe layed in the sand. Then I would use solar, or a rocket stove to heat the sand via the pex, then to pull the heat off the chamber I would use either the same pex or another pipe running thru the chamber via heat exchanger for like a shower..... I am still in the design stage in my brain, I have the pex, but I am waiting on finding a window to move forward with the design.

Excellent video.. When i was in HVAC class in the 80's the roof mounted water solar heating systems were still in use from the Carter years. We did something along these lines but using 1/2 copper tubing, (it was much cheaper then) as it was the only good quality tubing we had at the time. they come rolled so it was not hard to lay the roll on plywood, put some strap on in teh fashion you did and spray paint flat back.. We did not put sides or glass over it .. we sat it out in the back in sun and gave it several mins while hooking up a small pump to move water from a 5 gallon bucket.. the water was surprising hot in short order.. was trying to figure out a way to do this on my RV to help reduce LP usage..

 

[mpgmike]

I have been using a solar tube to cook with for some time.

Rand Solar vacuum cooker Modifications of Stand, end cap, Temp probe

Rand Solar vacuum tube cooker modifications

odysee.com

I have been watching what others do with these, one guy fills it with sand, then heats the sand, then poors the heated sand into a cooker then cooks on top of that heated sand like a thermal cooker. I am looking to build a hot water heater via solar in the design of Desert Sun has done...

I was thinking of building a chamber out of aircrete mixed with styrofoam, then in this chamber store sand with a pex pipe layed in the sand. Then I would use solar, or a rocket stove to heat the sand via the pex, then to pull the heat off the chamber I would use either the same pex or another pipe running thru the chamber via heat exchanger for like a shower..... I am still in the design stage in my brain, I have the pex, but I am waiting on finding a window to move forward with the design.

I had thought about the coils like shown, but I get hung up on trapped air. The evacuated glass tubes keep the lines vertical allowing any air to rise and purge. Also, if you're just running plain water through the coils, you will never be able to properly drain them when temps drop below freezing. The water that lays in the low spots in the coils may be the water that breaks the tubing when it freezes. We're replacing the windows in the house and I was thinking about building solar water boxes using the old glass. My thought was a series of vertical tubes with a bunch of T's top & bottom to form an upper and lower manifold. Cool water enters the bottom, hot water exits the top.

 

[Quattrohead]

You cannot use PEX in the sun as it will degrade. Use black irrigation type pipe