Need guidance on solar panels

[matthewsunshineflorida]

So this seems to be the best deal I can find on Heliocol 500sqft ($7,600):

Heliocol Premium Solar Pool Heater DIY Kit - World's Best Selling Pool Collector - High-Wind Mounting System

Heliocol systems are known for design excellence with a proven track record for efficiency, reliability, and safety. With a 12-year limited warranty including freeze protection, Heliocol Solar Pool Heating Systems are environmentally safe, low maintenance and roof friendly.

www.solarpoolsupply.com

However, the same company makes their own 500sqft design for $5700 which is clearly stolen by heliocol as it has the same mounting system, panel layout, and even 12.5ft dimension:

SwimJoy Industrial Grade Solar Pool Heater DIY Kit - Advanced High-Wind Mounting Security - Maximum Freeze Resistance

SwimJoy pool solar panels. Shop The Leading solar swimming pool heater for your home. DIY friendly solar pool heating system for your inground swimming pool or aboveground pool. From the same manufacturer as Heliocol solar panels. Max-Durability, Energy Efficient, Ultra-Secure Mounting for Storm...

www.solarpoolsupply.com

It looks like a well made panel to my eye based on the stuff I've seen so far.

Then I found the same kit from them on Amazon for $5600 but it also advertises a 15% off coupon which brought the total to $4800. Still not $2.5k, but it's at least a whole lot more reasonable especially given I'd have 500sqft for a 12-13k pool which should give me a lot of juice.

https://www.amazon.com/dp/B07VWMZV7H

Downside is it's an Amazon coupon which means it could easily go away any day and my pool won't be done for a couple months. But it's $850 off which is hard to resist. If I save $100/mo in gas, my payoff is 4 years plus I'd likely have a longer swim season and I could probably get it to exactly the most comfortable 86-88 temp during the summer and some of the spring/fall. I think I'd do anything under an 8 or so year payout. My roof is 4 years old, so I'm thinking it could at least last until that replacement and maybe longer?

You guys talking about gas heaters failing so quickly makes me feel like I should baby it and use it mostly for the spa and go solar for the pool.

The last thing that makes me nervous is holes in my roof. How do you ensure you hit the joist when you can't use a stud finder through shingles? Also, why do none of these systems appear to have flashing? It seems like we're just going to trust whatever sealant we put in the hole and on top of the screw after putting it in? No other roof protrusions are trusted in this way - that seems really odd to me.

Any other wise words or thoughts on this?

EDIT: Heliocol claims significantly greater performance than SwimJoy, although the difference may not be drastic enough depending on how often we're in the ABCD categories:

Why SwimJoy?

Thanks to the reliability and durability of our state-of-the-art system, you can enjoy your swimming pool for more than just the summer months! Performance & Features Individual tubes enable your roof to “breathe,” which prevents moisture from being trapped under the collector. Tubes...

swimjoysolar.com

https://customsolarandleisure.com/wp-content/uploads/2017/05/heliocol-tech.pdf

 

[Dirk]

So this seems to be the best deal I can find on Heliocol 500sqft ($7,600):

Heliocol Premium Solar Pool Heater DIY Kit - World's Best Selling Pool Collector - High-Wind Mounting System

Heliocol systems are known for design excellence with a proven track record for efficiency, reliability, and safety. With a 12-year limited warranty including freeze protection, Heliocol Solar Pool Heating Systems are environmentally safe, low maintenance and roof friendly.

www.solarpoolsupply.com

However, the same company makes their own 500sqft design for $5700 which is clearly stolen by heliocol as it has the same mounting system, panel layout, and even 12.5ft dimension:

SwimJoy Industrial Grade Solar Pool Heater DIY Kit - Advanced High-Wind Mounting Security - Maximum Freeze Resistance

SwimJoy pool solar panels. Shop The Leading solar swimming pool heater for your home. DIY friendly solar pool heating system for your inground swimming pool or aboveground pool. From the same manufacturer as Heliocol solar panels. Max-Durability, Energy Efficient, Ultra-Secure Mounting for Storm...

www.solarpoolsupply.com

It looks like a well made panel to my eye based on the stuff I've seen so far.

Then I found the same kit from them on Amazon for $5600 but it also advertises a 15% off coupon which brought the total to $4800. Still not $2.5k, but it's at least a whole lot more reasonable especially given I'd have 500sqft for a 12-13k pool which should give me a lot of juice.
https://www.amazon.com/dp/B07VWMZV7H

Two points:

My $2500 kit was eight 12.5' panels, not ten, so that helps your math a bit.

I know nothing about that Heliocol knockoff. Just be cautious (somehow?). Those pictures look identical to the Heliocol pictures, which might only mean they've swiped Heliocol pictures, not necessarily their actual design. Or maybe they're reselling Heliocol parts? Or refurbished Heliocol parts? Or buying the same parts from the same Chinese manufacturer? (I don't actually know where Heliocol parts come from.) Or buying parts from a Chinese knockoff manufacturer, as happens in other industries?!? None of those possibilities necessarily means anything is wrong with the parts, or they are not as good. What is their return policy, just in case a bunch of junk shows up at your door?

Downside is it's an Amazon coupon which means it could easily go away any day and my pool won't be done for a couple months. But it's $850 off which is hard to resist.

Well, that just means you could install the system now, and have the pipes ready and waiting at the pad for the plumber to hook it all up for you when he does the rest of your pad. That's a good thing.

If I save $100/mo in gas, my payoff is 4 years plus I'd likely have a longer swim season and I could probably get it to exactly the most comfortable 86-88 temp during the summer and some of the spring/fall. I think I'd do anything under an 8 or so year payout.

86-88 is probably realistic. I can mostly do that, well 86 anyway. It has a lot to do with nighttime temps. My nights cool off due to coastal influences. That tanks my water temp each night, which definitely affects how well I do the next day. Without that factor, I'd probably be in the upper 80s or low 90s. And get a longer season, too.

My roof is 4 years old, so I'm thinking it could at least last until that replacement and maybe longer?

What is the expected lifespan of your roof? There is a school of thought that the panels extend the life of the roof, as they block the UV somewhat. I don't have hard data on that.

You guys talking about gas heaters failing so quickly makes me feel like I should baby it and use it mostly for the spa and go solar for the pool.

It's not clear if longevity is equal to hours of use or what. Someone mentioned water quality as a big factor. You could have the plumber install a heater bypass. Maybe by not running water though the heater in the off season, or even blowing it out somehow, you could extend its life? That's pure speculation on my part. A bypass for the off season would save on pump energy a bit, because heaters can impede flow significantly.

EDIT: Heliocol claims significantly greater performance than SwimJoy, although the difference may not be drastic enough depending on how often we're in the ABCD categories:

Why SwimJoy?

Thanks to the reliability and durability of our state-of-the-art system, you can enjoy your swimming pool for more than just the summer months! Performance & Features Individual tubes enable your roof to “breathe,” which prevents moisture from being trapped under the collector. Tubes...

swimjoysolar.com

As I mentioned, I don't know what to make of each manufacturer claiming better performance than the next. I suppose quality of material and overall design must affect performance by some amount, but by how much? As I said, they're all black stuff on a roof with water running through them. How different can they be in heat generated? Now longevity, wind resilience, connection quality, mounting systems and warranty can be radically different from brand to brand, but heat generated? Not seein' it...

The last thing that makes me nervous is holes in my roof. How do you ensure you hit the joist when you can't use a stud finder through shingles? Also, why do none of these systems appear to have flashing? It seems like we're just going to trust whatever sealant we put in the hole and on top of the screw after putting it in? No other roof protrusions are trusted in this way - that seems really odd to me.

Any other wise words or thoughts on this?

I mentioned penetrations a bit in a previous post. What type of roof do you have? If it's a tile roof, you don't need to penetrate the underlayment materials at all, or seek out the rafters. The brackets connect only to the tiles. If it's an asphalt shingle roof (or a tile roof for that matter), there will be a plywood underlayment beneath the shingles. I think those are usually 3/4" thick, maybe less. Anyway, you'd be screwing into that, again no need to find the rafter.

So far, in my regularly occurring 15-25 MPH winds, no issues with attaching only to the tiles. I think that is in part due to the Heliocol design, the individual tiny tubes. They do let some of the wind energy pass through them. It's less prone to wind forces than say a solid sheet of material, like some panels. It's important to note that that was the recommendation for my locale. If your area is subjected to very high wind loads (like hurricanes?!), then that could racially affect what you need to do for your installation.

Regarding sealing the screw holes, I used a proper roof sealant. For tiles, it matters little, because any water that managed to get past that sealant would fall onto the roofing felt, and then drain down to the gutter under the tiles. It still wouldn't get to the wood, or the attic, because there's no penetration. There would be penetration for a shingle roof, but remember, every shingle on a roof has several penetrations anyway, the nails (or staples) that were used to affix the shingle to the roof all penetrate the shingle, the felt and the wood, right into the attic. Those get "self-sealed" by both the shingle and the felt. Any screws you used would also be sealed in that way, and then additionally protected by the sealant you would apply on top of that. It's really a non-issue. The only problem you'd have is if you backed out the screw for some reason, and then screwed it back in. That would compromise the self-sealing properties of the shingle/felt system, so don't do that. Plus, any screw holes holding the brackets down are under the brackets. So you goop the bracket bottom, then drive the screw in. That kinda seals the bracket to the shingle, and surrounds the penetration at the same time. And the sealant is now under the bracket, which protects it from UV. Again, as long as you don't back out the screw, or move the bracket and leave an uncovered penetration, you'll be fine. And even if you have to do that, the right sealant will fix any inadvertent holes you might make, as those sealants (the good ones) will outlast shingles. If you make inadvertent holes in tiles, you seal them up the same way, but again, water that makes it through a tile can't get to the attic, that's what the roofing felt is for.

Similar to how it's the plaster that makes a pool waterproof, not the gunite, it's the roofing felt that makes a roof waterproof, not the tile or shingle. The primary job of the tile/shingle is to keep the sun off the felt. As long as the felt doesn't dry out and degrade, the roof remains watertight. Yes the tile/shingle sheds water, and adds to the overall waterproofing, of course, so you protect it, too, but the layers of roofing materials are redundant, and back each other up.

 

[matthewsunshineflorida]

Now those panels are on sale with a 20% coupon bringing 500sqft of panels (to heat 460sqft of pool/spa) to $4.5k no tax or shipping - meaning I'm probably under $4800 for the other pipes/valves so payback could easily be 4 years. By FAR the best deal I've seen on panels that don't look cheap.

https://www.amazon.com/gp/product/B07VWMZV7H

I have a shingle roof 6/12 pitch with rafters 24" on center and relatively thin OSB over top. I really do not trust the thin OSB alone to hold panels watertight in a wind storm - I would think vibrations over time would cause small openings around the screws which could let in water. So I'd want to put them RIGHT on the rafters which this kit does seem to be designed to do (clips can be spaced 24"), sealant inside the holes and over top of the screws and I think I'd be set. Might have a little trouble finding that first stud but should be able to measure off from there...

I have so many projects to do so I'm wary of adding this in, but the videos honestly make it look like I could mount these in a weekend. I'm tempted. Wife wants me me to wait and see what the gas bill looks like but I feel like it is almost guaranteed to eventually pay for itself, and our roof isn't even 4 years old so we still have a lot of life out of it. Hmm...

 

[Dirk]

All good!

Measuring from the first rafter is supposed to work, but it's not a given. Depending on how your roof is built, you should be able to see the rafters under the eve. That will give you the first rafter, plus you can measure the others to confirm they're 2' on-center. If they're hidden by a soffit (a kind of "ceiling" under the eve), you might be able to find nail heads in either the soffit or the facia that would indicate where the rafters are. If neither of those ideas work, I have a few others...

 

[Dirk]

Sorry, I just realized I've been stomping all over aislephive's thread. If this info isn't helpful I can have a mod fix my hijack...

 

[matthewsunshineflorida]

All good!

Measuring from the first rafter is supposed to work, but it's not a given. Depending on how your roof is built, you should be able to see the rafters under the eve. That will give you the first rafter, plus you can measure the others to confirm they're 2' on-center. If they're hidden by a soffit (a kind of "ceiling" under the eve), you might be able to find nail heads in either the soffit or the facia that would indicate where the rafters are. If neither of those ideas work, I have a few others...

Yea my rafters are covered by soffits and then gutters so no real way to get to it from there. But I was thinking what I can do is go to the attic and measure off the wall, put a rare earth magnet right in the attic against the OSB right next to the first rafter... then measure the same distance up top and I should be able to drag a magnet up until I find it, then the rafters are 1.5" wide so go over 3/4" from the end of the magnet. Then I'm thinking I'll just measure the distance between each rafter from inside the attic to make sure I hit the center on each one (or do the magnet idea each time?). I like the clip on system so I'll probably do helicol or those knock offs - $5k seems reasonable for something that looks like it could last a really long time, especially since we only have 425sqft of pool plus the spa maybe 450-460 with 500sqft of solar should really make it comfortable most of the year, seems so worth it.

However, I had a sit down with the wife who is pretty set on a hard no until we get the pool done and all the landscaping/bar etc finished. Doesn't like so many things undone and wants to stop depleting our cash reserves. So this would be spring earliest, maybe even fall (definitely not summer).

So I'll get back to you on the solar - in the meantime focusing on the build! Electricians are here today running conduit for the lights...

 

[Dirk]

I haven't heard of too many builds that don't somehow, mysteriously, end up with cost overruns. Sometimes upgrades. You name it. Sounds prudent to be cautious with the funds. No worries, she'll get on board the first time she gets chilly!

But you can have the PB plumb for the future system now, which will save you the cost or hassle of doing it later. Pool pads can get tight, so stubbing in the solar pipes now will save their spot, so to speak. The plumber can form a loop in the system, which you can later cut out and glue in your solar valve and check valve, and then continue on from those to the roof.

No luck finding any nail heads in the soffit? Did they stucco it?

If you have access to the attic, then measuring from the inside is a solid idea. With today's fast and furious profit-driven construction techniques, you can't always count on the laborers measuring everything perfectly. Your magnet idea sounds interesting. An alternative is to look for any existing penetrations and use one or more of those as your marker(s). Any roof jacks, or HVAC vents or plumbing vents sticking through the shingles anywhere near where your panels are going to be? You could measure each rafter inside the attic off of one of those. Chances are one of them will be strapped to a rafter, making it even easier to find up top (similar to how electrical outlets are nailed to studs).

 

[galatorre]

+1 for Heliocol. Quality, best coupling technology I could find. Wind and expansion is all handled by the excellent design. I checked out Aquatherm EcoSun's website, but couldn't ascertain much. It's a pretty lame site: missing images, no user/installation manual, no closeup pictures of the panels, etc. I was trying to see how their panels connect. If it's the "radiator hose and hose clamp" method, steer clear. Heliocol uses an o-ring that is encased and out of the sun. Their mounting system is great. I installed myself and saved 70%! I think the warranty is 20 years.

If you decide to use your south-facing roof area, be certain you'll never want to install PV solar. I used the north-facing side for my pool heater, and saved the better south-facing side for my PV solar. Pool solar is more forgiving that PV when it comes to sun angle.

I also used black UV PVC, which was superior to white or white painted black. The black faded a bit, but it's still way better looking than white, and way, way, better looking than peeling paint (painted pipe won't last long on a roof). So be sure to ask your installer what they use for pipe.

I'm just about to decide if I should install Heliocol or Auqatherm solar panels? Are you still happy with your Heliocol system? Would you say it was the best decision in your case?

Thanks.

 

[Hypoxic]

I have 10 4x12 Aquatherm panels and they have been great. I installed them 5 years ago and haven't had any issues.

 

[galatorre]

I have 10 4x12 Aquatherm panels and they have been great. I installed them 5 years ago and haven't had any issues.

Thanks for the reply. It's good to hear you haven't had any issues. I think I'll go for Aquatherm as well. My soup will also have 10 4x12, I 'll let you know how it goes. Cheers.

 

[Hypoxic]

Thanks for the reply. It's good to hear you haven't had any issues. I think I'll go for Aquatherm as well. My soup will also have 10 4x12, I 'll let you know how it goes. Cheers.

Nice! I went with 2" collectors to maybe reduce some flow restrictions. I see a 5-6psi rise at 50 gal/min when the solar is heating. Just circulating the water without solar it 0 psi at 30 gal/min.

 

[matthewsunshineflorida]

Our gas bill is easily $100 more and that's just heating the pool on the weekends and spa once or twice a week.

These panels are now $4300 for 500sqft and I'm pulling the trigger:

SwimJoy Industrial Grade Solar Pool Heater DIY Kit - Advanced High-Wind Mounting Security - Maximum Freeze Resistance

SwimJoy pool solar panels. Shop The Leading solar swimming pool heater for your home. DIY friendly solar pool heating system for your inground swimming pool or aboveground pool. From the same manufacturer as Heliocol solar panels. Max-Durability, Energy Efficient, Ultra-Secure Mounting for Storm...

www.solarpoolsupply.com

I feel like I have most of my questions answered, but there's one I don't have a solution to yet: I've seen photos of black PVC warping and leaking. I've read that a huge part of this is when there is water sitting in the panels that can't escape and it reaches very high temperatures for long periods of time. This is why panels are designed to drain automatically when the pump turns off. However, with our intellicenter, I can imagine that in mid summer it's going to quickly heat to 88 by noon or 1pm, and then the pump will stay on preventing the solar heaters from draining while the temps in the pipes soar. The only way I can think of solving this is to manually turn off the pump when it hits temp.

1) Is painting PVC black really that big of a problem?

2) Is the water staying in the pipes really a big problem?

I guess either way, it's just cheap PVC and I could replace it in 5-10 years without much hassle, but I don't want to have white PVC unless I have to - and I'd really like for the whole system to last as long as the 4.5 year old roof (another 15-20 years?).

 

[Rocket J Squirrel]

I've read that a huge part of this is when there is water sitting in the panels that can't escape and it reaches very high temperatures for long periods of time. This is why panels are designed to drain automatically when the pump turns off. However, with our intellicenter, I can imagine that in mid summer it's going to quickly heat to 88 by noon or 1pm, and then the pump will stay on preventing the solar heaters from draining while the temps in the pipes soar. The only way I can think of solving this is to manually turn off the pump when it hits temp.

Your fears are unfounded. You will have a 3-way valve with an actuator controlled by the Intellicenter. That valve will send water to the solar panels, or not, as appropriate based on temperatures. Your assumption that "panels are designed to drain automatically when the pump turns off" is incorrect. When the solar is disengaged, the vacuum relief valve(s) will allow air into the system, letting some water drain down the pipes even while the pump is running.

 

[willygee]

Informative post...my roof perfect exposure here in central Fla.

 

[matthewsunshineflorida]

Your fears are unfounded. You will have a 3-way valve with an actuator controlled by the Intellicenter. That valve will send water to the solar panels, or not, as appropriate based on temperatures. Your assumption that "panels are designed to drain automatically when the pump turns off" is incorrect. When the solar is disengaged, the vacuum relief valve(s) will allow air into the system, letting some water drain down the pipes even while the pump is running.

That is great news, but I'm having trouble understanding how that is the case. Do you mind reading my understanding of how this works and let me know what I'm missing (or if the design needs adaptation)?

The "Return" side of the plumbing comes out at the top of the panels, and the "Feed" side is at the bottom. This means the panels themselves can only drain through the feed side because gravity would prevent it from draining UP into the return side, so only the water in the return side pipe can drain down the return side.

When the feed side 3-way valve is turned off to block the feed and open up the bypass, the water goes directly to the return side. It would attempt to push both down toward the pad and up the return side toward the panels, but there's a check valve to prevent this from happening. However, that means this check valve keeps that side closed altogether - preventing the pump from pushing water up the return side and also preventing the return side from draining. Similarly, the 3 way solar valve has a reverse check valve on the closed feed side, which will only allow water to go down when closed. When the pump is on, you'd think the pressure would keep this check valve closed, preventing the feed side from draining.

Seems like, when the pump is on, neither side can drain at all because both check valves are closed due to the pressure of the water.

What am I missing? Appreciate it! Just want to do it "the right way" so I get as many years of trouble free operation as possible. I'd really like to paint the PVC black, if at all possible...

 

[matthewsunshineflorida]

@Dirk by the way, I noticed something pretty fascinating about these panels vs Helicol. TLDR: They're the same!

The clamp system is patented so I was wondering how it was possible for them to copy and sell this design in the states like this. I downloaded both installation manuals and realized something: They are IDENTICAL. The wording, the page numbers, the photos. I had previously read they were made by different manufacturers so I'm thinking what the heck - Chinese knockoffs that somehow can't get sued?

Nope, it's far more simple (and good) than that: Helicol panels are made by UMA Solar. SwimJoy panels are advertised as being made by Magen Eco Energy starting in 2018. How? Well in 2012, Magen acquired 100% of UMA solar and is simply white labeling the Helicol panels to target a lower price point through SolarPoolSupply, which they also own. Instead of wholesaling Helicol to dealers, they can sell SwimJoy branded panels direct to consumers to compete with other online sellers, all at a similar profit margin as Helicol's dealer program - without diluting their Helicol brand.

Those Israelis are smart! One of my favorite places I've visited - their ingenuity to thrive in the desert is pretty amazing.

 

[Rocket J Squirrel]

Similarly, the 3 way solar valve has a reverse check valve on the closed feed side, which will only allow water to go down when closed. When the pump is on, you'd think the pressure would keep this check valve closed, preventing the feed side from draining.

I'm unfamiliar with this setup. My solar has only one check valve, to prevent water from going back up what you call the return side. When the solar is disengaged, this check valve allows water to drain until the pressure from the valve spring is stronger than the draining water pressure.

 

[chiefwej]

The three way valve for solar is different from your other pool three ways. It has a very small valve in the gate that allows the panels to drain back down when the solar loop is shut off.