I am planning to put in a closed loop system (gycol ) myself to save a few thousand . How difficult is it ? I suppose it would not be too difficult once I get the panels up . Any things I need to look out for? thanks

malibud
Read the mother eart news book on solar hot water. It was a big help to me.

I am past the point of no return on my system. I purchased a 40 tube system from Silicon Solar in NY (horrible cust. service). I just installed the manifold racks on the roof and have the heat transfer tank plumbing almost done. I used PEX on the DHW side and all copper on the solar loop side... My real concern, other than what the building inspector will think of my install of the solar racks, is my soldering job. I have a sick feeling that when I test the system there will be leaks all over the place... If I have time I will post some pictures of what I have done.

You should pressure test with air before you try to fill with water - it's a little less messy and you can see whether it leaks easily by using a pressure gauge. Finding the leaks is a little more difficult, but a squirt bottle with dish soap and water is pretty effective. When I was working building leak detectors professionally, we could test for leaks that were smaller than a human hair, you could still see those easily on a bubble test.

I have PEX on the solar side. I have some long tubing runs to the storage tank and installation is easier than copper. PEX is rated for 200F in heating systems, and I think I'm in trouble if I end up with water much hotter than that. The last couple of panels should be in place this weekend and so I'll be in test mode shortly thereafter - I'll post the outcome. The design basically follows Gary's for underfloor radiant heating.

I think that you've hit the nail on the head that mounting is probably at least as difficult as plumbing. Panels are heavy. I have them on a ground-level A frame, 4 high and eight feet wide, but this means that the highest panel is 12ft up. We had four people, a block and tackle, ratchet straps and finally two car jacks for final fine positioning on the highest panel - took the better part of an afternoon. Mounting on the roof may be easier, but you have to get them up there first!

All pressure tested, found one leak, had to cut part of the flex 3/4" flex copper where it crimped and solder a union around it. I have it running at 32 psi with about 60 -65% glycol (food safe) to H2O. It boiled out only once and it was due to my human error. I had closed the loop with the charging valve and forgot to open it when the pump came on the glycol/water stayed in the heat pipe ant the collector for over an hour and tripped the pressure and temp valve. I was able to replace the valve and recharge the system in about an hour.

Here are some pics

sorry how large the pics are, I tried to save at low quality but the size I could not control...

Looks great! Any tips to share (don't boil the system?).

Silicon Solar out of NY was useless as far as post purchase help. I still am missing the real tank sensor. They sent me a "lug" type for the tank. I have filed a request with my credit card co. (AMX) for them to look in to Silicons price and sayng it was just "Plug and Play" meaning ready to install. The instructions for set up and installation of the solar panels were barely legible. No real plumbing instructions. I searched the web for 95% of the plumbing diagrams. And had to find, on my own boiler antifreeze (the food safe glyco). What makes me happy is that I was able to still get it together and working. Even with the poor customer service from Silicon. The evacuated tube set up is great though, the mounting frame is light enough, my 11 year old son and I got each on the roof no problem. Then we just took our time bringing up each tube. You do the tube install after all the plumbing is done.... I was also impressed that I was able to wire the pump and controller with out incident.(electrocution) I am a doctor of optometry so plumbing and electrical are not really in my comfort zone...

Unfortunately, I can understand Silicon Solar's problem. As far as basic plumbing goes, there are so many possible configuration that if they provide the tubes at a competitive price then the tech support would eat up their profits. It is a good idea for companies to produce decent documentation because that saves people calling to ask questions and that might as well include "typical" plumbing configurations, and there's no real excuse for badly printed documentation. It does seem that they produce a good product, so updating the documentation would be worthwhile.

I have no recollection of how I functioned before I could look up much of this information on the Internet, it certainly does make project like this accessible by providing guidance and help.

What is the brand of the differential controller in that picture above? A GoldLine with the cover off?

Yup gold line with cover off. I wish they still made the lcd plug in. I would like to know the storage tank temp...

Why did you use the evacuated tube type panel? I think it's more efficient but it kinda stands out more. I don't mind because I think it looks cool, but...My girl would kill me.

The soldering you did do is pretty good though...for a doctor! Kidding, kidding, great job.

Mark
http://www.greenscollar.com

Mark,

Aesthetics are a funny thing. There are really ugly utility poles all around us, but you suggest adding one cell tower and everyone is up in arms. Where I live, steel roofing, for fire resistance, is the norm and no one complains of the appearance, but in other areas that would definitely be considered ugly. So it's somewhat a matter of acceptance and the norms. Let's hope that we can reach the point where only houses that have solar systems are considered aesthetically pleasing.

So you can tell your girl that she can be out in front of the fashion curve, just by saving the environment and money on the utility bill by adding solar collectors. You might want to put some pillows and blankets on the couch before you suggest it - just in case.

I knew that I wanted it to be at 50 deg. angle. ( the roof faces due south, checked with my wifes garmin nuvee). So at that angle any panel would be obvious.... I think the Tubes look good and I did my best to hide the pipe behind the heat manifold. and the main "Cape" roof line obscures a bit of the thru the roof plumbing... And yes the evacuated tubes are suppose to be better in colder climates. ( we are in Granby CT) We will see. We have had 2 sunny days back to back and I believe have gotten good production.

Hi,
You might be interested in this DIY solar water heating system for cold climates:
http://www.builditsolar.com/Experimental/PEXColDHW/Overview.htm

It aims to provide a good, cold climate solar water heating system for less than $1K -- plus a fair bit or your labor :)

The prototype has been in operation for a month with 100% solar heating and no problems (so far).

Gary