Please Help ! Looking for a Horizontal Stainless Steel Solar Tank about 80 Gallon

[J.P.M.]

JPM - thanks a lot for your ideas, I appreciate your time.
I will be changing the whole system, the previous tank was from Turkey and not the best quality, it corroded (several leaks on the metal pipes I connect to) for hot water out. Plus the crud in the pipes has also cause 50+ pin hole leaks in the solar panels so now my panels leak about 5 gallon a day into the gutter. The system is on its last legs but still gives me enough hot water to survive but we have no electric back up and the wife is complaining about luke warm showers !?!
A 5 to 6 year change out seems quite often to me, I was hope to find a 10+ year solution but maybe I am being naive ?
If I could find that Australian solution in the States or even who makes it in China then I would buy it in a second. Or if anyone has any other ideas I would love to learn. I just saw a video on sopal tankless system - not sure if anyone used them in a warm climate ?
Cheers,
Mark

You're most welcome.

If you are in a warm climate, that is to say, one where freezing WILL NOT occur, a batch heater or a thermosiphon heater of the type you seem to have or have in mind is a good choice, and about the only choice if power for pumping is not available. Anyway, if local conditions or water quality causes problems such as corrosion, it will happen with any type system.

I might suggest a look at "builditsolar.com". Lots of ideas for DIY solar water heaters and a good primer on the subject. I've built a few solar water heaters in the past including a "breadbox" heater that used a recycled domestic water tank. Low tech. Just a few principles to keep in mind. Relatively easy to make from used/surplus material. Cheap. Appropriate technology (a term that seems to have become an anachronism).

Good luck.

[juakali10]

JPM - thanks a lot for your ideas, I appreciate your time.
I will be changing the whole system, the previous tank was from Turkey and not the best quality, it corroded (several leaks on the metal pipes I connect to) for hot water out. Plus the crud in the pipes has also cause 50+ pin hole leaks in the solar panels so now my panels leak about 5 gallon a day into the gutter. The system is on its last legs but still gives me enough hot water to survive but we have no electric back up and the wife is complaining about luke warm showers !?!
A 5 to 6 year change out seems quite often to me, I was hope to find a 10+ year solution but maybe I am being naive ?
If I could find that Australian solution in the States or even who makes it in China then I would buy it in a second. Or if anyone has any other ideas I would love to learn. I just saw a video on sopal tankless system - not sure if anyone used them in a warm climate ?
Cheers,
Mark

[J.P.M.]

Are you considering replacing only the tank or the entire system ? The link you included is for an entire system.

If you haven't done so alrady, I'd make sure the problem was a leak in a tank, and not someother problem (BTW, most often, tanks leak at a seam).

If I was considering replacing just the tank, and depending on the PITA factor(s) associated with a tank changeout, and after comparing the relative costs of a st. stl. tank vs. a more std. c, stl. tank, I'd consider investigating the idea of staying w/ a more std. (c. stl.) material tank and planning on a changeout at some regular interval, say, 5-6 yrs.

As for an American sourced vs. Australian or other origin tank, as long as there is a way to verify that the tank was designed, mfg'd., Q.C.'d and tested to a recognized code, the safety and quality of pressure vessels such as tanks are pretty much the same. Just get a tank that comes with a birth certificate (also known as a code stamp).

Q: Has the tank actually failed (sprung a leak ) ? Or, has the system simply stopped working or just overheating and so lifting the Pressure/Temp. relief valve from low/blocked flow due to fouling/crud buildup in the system ?

Thermosiphon type systems such as you seem to have work well, but the flowrates are usually low relative to pumped systems. Depending on the application, local conditions including H2O quality, and other details, such low flowrates can cause things to crud up more quickly.

All that said, SDHW service for batch heaters is not considered a severe or particularly critical application.

If the tank has indeed failed from fouling/corrosion of some sort and failed, while you're at it and before getting a new tank, it may be worth checking out the condition of the rest of the system components such as valves, elbows, the flat plate collectors other system components or places where dissimilar metals are joined for other possible and similar problems.

Just a note: 304 st. stl. has most all of the same corrosion resistant characteristics as 316, particularly for less severe duty such as solar DW heating, but may be slightly less expensive.

Also, and although probably not a consideration for this application, where using st. stl. might be considered by some as analogous to killing flies with a howitzer, note that st. stl. is not corrosion resistant to everything.

[juakali10]

Hi folks - a newbie here so I apologize if asking a dumb question but I am stuck !?!
I have two flat plate solar collectors that I want to connect to a stainless steel tank, the system runs off mains pressure. I am based in the Turks & Caicos Islands so its a direct system but the water is RO and poor quality, my last mild steel tank (enamel coated) but rotted through in 6 years so now looking for a stainless steel tank 316 stainless (with about 2 inch insulation). Importantly the tank must sit horizontally on my roof, above the panels. I can find exactly what I want in Australia http://www.ecosmart.com.au/products/roof-mounted but was hoping to find an American version. Does anyone know if this is possible ? Or, if anyone has any advice I am all ears to listen and learn. Thanks very much ! Mark