Jabba

A little more info, and perhaps easier to comment on than all my dribble above. At about 42 GPM I see a 4 degree temperature rise from 80 entering the panels to 84 exiting. The panels are rated at 47K BTU/day and I have 6. Does this sound right? Does anyone know the formula for calculating the expected temperature rise?

Just installed some aquasol 4x12 collectors, 6 of them on a south facing roof in San Jose, CA for a total of about 288 sq. ft. Pool is 14x36 kidney shaped with about 430 sq. ft. surface area with no solar cover. Weather the last few days has been mid to high 70's, low high 50's with low wind (< 10 mph), mostly sunny with partial hazy clouds. Unfortunately I don't know what the pool temp was before the install, guessing mid 70's. Now that I'm measuring it I see about 81 in the morning and 85 in the afternoon for the last two days. Is this about what I should expect? Thanks.

Just want to confirm the configuration of the plumbing up onto the roof. I was planning on just running new pipes based on the old configuration: Should I just plumb the new pipes the same way? Or should I run them along the W side of the house and then up the wall so they don't have to travel over the ridge? And why is drainage not really a concern on this setup? Is it mostly a concern with freezing, which we don't get in SJ during swim season of course. What about the extra weight always sitting on the roof? Thanks.

I've read a few of the solar panel installation guides and it seems that mostly white 2" PVC schedule 40 is recommended. I was at Lowes and they only seemed to carry DWV (drain/waste/vent) PVC in schedule 40, but it says it's not suitable for pressure. Clearly solar panel piping will carry pressure. Do I need to find schdule 40 that is NOT DWV? Is this stuff somewhat uncommon? I was surprise that lowes only had DWV. Thanks.

Thanks for the feedback. The SunGrabbers I'm looking at do include the relief valve and roof mounting hardware. So there doesn't seem to be any advantage/disadvantage to mounting horizontal/vertical? Regarding the plumbing, I think I understand the flow with the supply entering at the bottom corner, and the return leaving at the top opposite corner. WRT to drainage, my old system had the relief valve and all, but I think it was plumbed in a way that it never drained. The pool is in the back, the panels were on the front of the house. The supply and return pipes travel up the back wall of the house, then up the slope of the back part of the roof to the ridge, then back down the front where they connect into the collectors - supply on bottom left, return at the top right. It seems like the return pipe itself would rain, but I don't see how the collectors would drain as the water would have to run "up hill". Perhaps the water would siphon out the return pipe, with the VRV allowing air to enter the collectors. But I can't believe this would allow all the water to drain? How does drainage work on a typical system? If my pipes travel over the ridge of the roof like this, will drainage work property for me? Thanks.

Reviving an old thread here. Getting close to purchasing solar collectors. Naturally I turned to the internet first. I've been leaning towards Fafco, and the Sungrabbers are sold in a few places online for a reasonable price, free shipping, no tax, etc. You mentioned that Sungrabber are typically for above ground, however I see them advertised as both, and the online retailers seem to advertise them mostly as in ground application. Is there typically a difference in the construction, sizing (i.e. 2' vs 4' width) or otherwise for in/above-ground collectors? Sungrabber seems to be made by fafco, but advertised and sold as its own brand, and is more readily available online. Can someone tell me exactly what the difference is between these and say the Fafco sunsaver collectors? Finally, collector size and orientation. I see most installations as vertical 4' x 10/12' collectors. My roof is approximately 28' width by 18' height with a normal (not too steep) slope. A horizontal installation of 2' x 20' (sungrabber) seems to have a better cost/value. E.g. 8 - 2' x 20' collectors would yield 320 sq. ft. of surface area, which would require 13 - 2' x 12' collectors. It seems sunsavers come in a max 4' x 12' size, so I guess I'd have to go with a vertical installation with a higher cost. So, vertical vs. horizontal? Thanks for the info.

Well I'm in S. San Jose, so not far from you. Do you recommend a local retailer where I can purchase them? Thanks.

I have an in-ground swimming pool that currently has solar collectors on the roof of the house. There are 11 collectors that are approximately 4x5', and they are constructed of of individual 1/4" hoses (similar to drip irrigation hoses). The collectors are quite old and many of the hoses have sprung leaks. I've repaired lots of them with drip irrigation fittings, but I think the collectors have about had it and I feel like that kid that keeps poking his fingers in the dam to stop the leaks. Photo of existing collectors: In the spring I'd like to demo the existing collectors and put up a new set, so I'd like to get some advice on which brand. The ones I have now seem quite cheap and prone to deterioration and breakage with all the individual tubes, and there's quite a lot of pvc/abs, collectors (11), brackets, etc. to make what seems like a somewhat complicated and visually unattractive system. In their place I'd like to have something that looks a bit nicer, is more durable and just as (or more) powerful. I came across these Vortex 4x12' Collectors that look pretty slick. They're a polypropylene plastic extrusion so they appear virtually flat across the top of the collector, but have elliptical tubes on the inside. They also come in 4' wide collectors, while a lot of the others I've come across are 2' wide so you have to connect more together to make up the same sq ft. To me the Vortex seem more durable with this plastic extrusion, I think they'll look better with the flat surface, and I also think a lower number of 4' wide collectors across the roof will look better and offer a simpler install with lower number of failure points. Sungrabber seems like a popular brand, but they have 2' collectors and the surface appears to be ribbed where the tubes are fused or molded together. Although I think I did read somewhere that the curvature of the tubes can collect more sun since part of the tube is always facing the sun as it arcs across the sky. Not sure if there's any truth to that. So please give me some feedback, and anyone who has experience with these Vortext collectors please let me know. They seem to only be available from Solar Direct and are a couple hundred bucks more than the Sungrabber.

For what it's worth, I actually find this saga quite entertaining...and educational. We have a plaster/gunite inground pool that I don't think has been resurfaced since 1970 and we're gonna have to bite the bullet here pretty soon. No plaster delamination, but the pool inspector said the previous owner kept the acid level too high and it stained the plaster with the copper from the pipes. Tiles, coping and deck have also seen better days. So I'll stay tuned to your saga and wish you the best! By the way, you just need a 3rd company to advise you so you have a majority. Hopefully there's not a 3rd option they can tell you!

No, the bleed tube or assembly is inside the filter tank and is supposed to bleed off any air that gets in the tank. Depending on your particular filter tank, it could be a tube or an assembly that is connected to the header that keeps multiple cartridges bundled. Okay, now I know what you're talking about. I have a cartridge filter with four cartridges bundled together and held in place at the top with a bracket. I'll keep an eye on the filter and see if it's bleeding off air properly. If not I'll pull it apart and see if I can figure out how to clean this assembly. Thanks.

I didn't clean the bleed tube screen. I assume that's part of the gauge and bleed assembly at the the top of the filter? I don't believe the solar panel is backwashing as there is a one way automatic valve on the pipe leaving the filter that keeps water from backwashing from the solar panel, and the valve seems to be working properly. I did replace the o-ring on the motor filter cover, then started up the pump and opened the bleed valve on the filter and quite a bit of air bled out until water started coming out. I let it run for a bit and when I shut it off I didn't get any backwash this time. Hopefully this was the problem and the filter stays bled properly. I'll keep an eye on it. Thanks for the advice!

Hello all, I have a problem with an inground pool with a self-priming pump, plus a booster pump (for pool sweep), solar panels on the roof and a cartridge filter system. When I switch off the main pump I get a substantial amount of water combing back out (backwashing?) of my skimmer. I would say it's probably a few gallons, sometimes enough to push the lid off the deck, but usually just enough to wash all the leaves and debris out of the basket and back into the pool. I noticed a few interesting things: * My self-priming pump with the filter basket and clear lid (sorry, not sure what this piece is called) does not seem to seal perfectly. I can't say for sure if it draws in air (probably?) but when I switch the pump off and the backwash occurs water leaks out from the lid due to the backwash pressure I assume. * There is an initial backwash that occurs when I turn the pump off and I hear some noise in the filter (air), then after a few seconds and some more noise in the filter a second stronger backwash occurs. * It takes a few minutes (probably 2-3) for my pump to fully prime. * After opening and cleaning the cartridges in my filter a couple weeks back, I noticed the clamp ring that holds the filter together was slightly dripping at one location. I have since tightened up the clap so the tension springs are touching each other (per instructions). It was slightly looser than this before. * I also have solar panels on the roof with a 3-way valve that can be used to divert all or a fraction of the water through the panels. There are two valves with clear lids in the system, one that keeps water from flowing back into the filter I assume to keep the solar panels intake side from backwashing back into the system. The valve appears to be operating correctly. The second valve is more mysterious to me and from what I can tell it keeps water from flowing into the exhaust (exit) side of the solar panels. Not sure what the purpose is, but it does close when I turn the valve off of the solar panels. I seem to get the backwash problem regardless of how I have the solar panel valve diverted (open, closed, partial). Now that I think about it, my best guess is that the leak in the main pump clear lid is allowing air to be drawn into the filter and the filter is not fully bled, which then allows the water in it to flow back out causing the backwash. Although I don't know how the air gets in there, perhaps the filter lid? Anyhow, sorry for the long winded post. I appreciate any suggestions you guys have. Thanks.