Solar Heater Help

[USFishin]

I got some solar heater panels off of Craigslist for dirt cheap and it looks like they're only a couple years old. They are stamped with a "Guardian - Protecting Your Lifestyle" logo and also have a sticker label on them that says "Solar Collector by Harter Industries, Inc" and a serial number. It appears that these "Guardian" panels are made by Aquatherm. Anyone have any experience with Guardian?

I've been doing a lot of reading on valve placement and stuff but still have a couple of questions. There doesn't seem to be much talk about the actual connections between the panels. Do you have to use connectors specifically designed and marketed towards solar panels or is there a DIY solution available at the local hardware store? There doesn't seem to be many places online that sell the connections and parts. Here's one I found that I am leaning towards http://www.bestbuypoolsupply.com/solar-panel-parts.html. I'm putting the panels on the flat roof over my patio and they will be in two sections. A section of the patio is an aluminum roof and another section is shingle. There's a divider between the two sections of roof that bumps up about 2 inches. So I need a flexible pipe to join the two sections and go over the divider. Could I use something like this http://www.homedepot.com/p/t/100211...word=223803&storeId=10051&N=5yc1v&R=100211638 to join the two sections of panels? Also, would something like that work for joining the panels together or would it be better to stick with one made for the purpose?

 

[JasonLion]

I can't help with most of your questions, but it is going to be very difficult to winterize the panels if the pipe pops up 2 inches in the middle of the run. That will prevent all of the water from draining out, leading to problems if you experience freezing weather. There are a couple of workarounds but most of them still require extra effort when winterizing.

 

[USFishin]

I'm not very concerned about winterizing because I am located in Oldsmar (Tampa, FL area). We might have one or two nights a year that we hit below freezing and it's usually only for a couple hours if that. That wouldn't be an issue would it? If I were to winterize the panels, I guess I could put a little valve at the bottom of the panels to drain the extra water out into the gutter.

 

[jblizzle]

I have added drains on my panels as well. Rarely below freezing, but I prefer to make sure they are empty all winter.

Posted from my Droid with Tapatalk ... sorry if my response is short

 

[davelinde]

My panels have a kind of an anti-siphon like thing at the highest point along with a check valve and the diverting valve cam'd to allow all the panels to drain back into the pool every time the pump turns off. It causes a bit of air each time the panel array charges up, but I thought this was the way it is "supposed" to be? For sure here we would never winterize anything - so I though the drains served another purpose. Not sure.

 

[JasonLion]

Ordinary manual valves on or near the panels are for winterizing. A vacuum release valve is for automatic draining each time the system turns off.

 

[USFishin]

So for what length of time can the panels (undrained) handle below freezing (upper 20's/low 30's)?

Does anyone have any comments on the piping?

 

[jblizzle]

I thought I installed my system carefully with everything sloping to drain when the pump was off. But I added a drain at the bottom of the panels. I was very surprised by the amount of water that still was in the panels and drained when I opened it up ... After having the pump off for days even.

Better safe than sorry I guess was my thought. There is no point in running the solar Nov through March since it will not warm the pool enough, so I just shut it down and drain it.

Actually I think you can run into issues if there is water sitting in the panels in the sun. It can get very hot and make the plastic get soft and possibly get crushed if there is any vacuum pulled.

Posted from my Droid with Tapatalk ... sorry if my response is short

 

[davelinde]

..I think you can run into issues if there is water sitting in the panels in the sun. It can get very hot and make the plastic get soft and possibly get crushed if there is any vacuum pulled.

I would expect that the plastic temperature would be the same (or perhaps even a bit lower) with water in it? The sun is heating the panel the same amount, with or without water inside and if the water does anything, it takes heat out of the plastic, it does not add it.

Still, the panels are designed to drain, so there must be a reason.

 

[JasonLion]

A couple of hours in the 28 to 30 degree range is usually fine.

At higher temperatures the plastic gets softer. If the panels are full of water they weigh more and if they are not completely supported the soft plastic plus extra weight will stretch the plastic and shorten the life of the panel.

 

[cramar]

THe panels definitely won't drain all the water unless they are rolled and the water is forced out - by that time your 1/2 way to taking them down anyways, this of course is assuming you have horizontal panels and not vertical.

I winterized my panels last fall and the amount of water that was left in them, despite having the vacuum release valve, was substantial.
Mine are rated for winter freezing and I rolled all the water out, the big question this spring will be how they fared - we have hard winters here.

 

[davelinde]

A couple of hours in the 28 to 30 degree range is usually fine.

At higher temperatures the plastic gets softer. If the panels are full of water they weigh more and if they are not completely supported the soft plastic plus extra weight will stretch the plastic and shorten the life of the panel.

ok that makes sense.
For my panels (fafco) I think it's OK to walk on them to service them... so with this in mind I guess it's also a good idea to run the solar a bit to cool the panels before attempting any servicing?
thanks... I like to learn how this stuff works - all quite new to me.

 

[cramar]

I wouldn't walk on them.

 

[jblizzle]

I have walked on mine (very little, like 1 or 2 steps to reach something and not when they are hot) ... but would avoid it as much as possible.

On a side note, had some of the coldest nights this winter in memory down here. Closed up the solar panel drain this weekend and fired it back up ... no leaks {well except for the slow drip from one of my PVC joints that I knew about last year after the install}

 

[Nova13]

on my fafco panels they use std looking black radiator hose like for a car.

Just standard hose without internal wire I will work.

You could also use exhaust hose from a marine store but that is over kill the water doesn't get that hot.

the entire bank of panels is supposed to tilted a bit to drain, if a little is left it will then have hopefully enough room to expand an not have a crack/leak.

 

[USFishin]

Some great info going on here.

I'm still thinking I'll need to get a kit like they have on here http://www.bestbuypoolsupply.com/solar-panel-parts.html because I'll still need the pieces that connect a standard PVC pipe to the panels. Unless anyone has another solution to connect a standard rigid PVC pipe to the panels?

 

[cramar]

Those kits will work, they are what comes with a full typical retail box.

Connecting PVC to/from the solar panels can be done with male/female ends, if you look at my build link and near the bottom of the pics I think you can see the same on my panels.
Solar panel > male/female PVC adapater > PVC pipe > PVC Union > PVC pipe

THe unions are optional but I really recommend.

PS, I've bought alot of stuff online from FlexPVC.com, they have a hughe inventory and good prices.

 

[USFishin]

Those kits will work, they are what comes with a full typical retail box.

Solar panel > male/female PVC adapater > PVC pipe > PVC Union > PVC pipe

PS, I've bought alot of stuff online from FlexPVC.com, they have a hughe inventory and good prices.

What are you referring to by the "male/female PVC adapter"? Looks like FlexPVC has a lot of good stuff. What did you use to go between two panels? My panels have 1 1/2" pipes on them but the barb on them comes out to like 1 3/4" (if I remember correctly, I'm at work now).

 

[cramar]

The kits you linked to will connect the panels together, another option is the right sized flexible rubber coupling (picture below), pretty common thing in a plumbing section, I used this on mine.

For PVC pipe feeding the panels, or exiting the panels, male/female adaptors will connect pipe to panel.

 

[USFishin]

I've seen those rubber PVC couplings but usually they say they're not rated for pressure. Usually they're just rated for drain pipe. Have you noticed them blowing up like balloons?