<div dir="ltr">Jason,<div><br><div>We had a similar situation with a SnapNRack UR-40 system. Homeowner said everyone once and a while they would hear a sound like "an acorn hitting the roof". It was pretty sporadic, but at least a few times a day. Install happened in late fall when there can be decent temperature changes throughout the day. Also, it was a cathedral ceiling below the install, so it's possible the sound was amplified by that (rather than being dampened by an attic). </div><div><br></div><div>All racking was installed as per SNR's specifications with gaps in the rail splices for expansion etc. Short edge of the panels were spaced so that they didn't touch each other. Talked with SNR and they didn't have any ideas. The install happened directly after some other work was completed on that roof section (cellulose insulation was blown in, new shingles, some new decking in places, drywall, etc) so couldn't be sure in the end if it was related to us or somehow related to any of the other work that had happened (although they didn't notice it until the panels went up). The engineer said maybe there was just some settling in the house due to all the work. Doesn't sound like it was nearly as extreme as your situation though, and we never figured out exactly what it was.</div><div><br></div><div>Adam</div><div><br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr">Adam Katzman<br>Autonomous Energies<br>PO Box 1245</div><div dir="ltr">Kingston, NY 12402<br><a href="http://www.autonomousenergies.com" target="_blank">www.autonomousenergies.com</a><br>(518) 567-1468<br><br></div></div></div></div></div></div></div><br></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Oct 19, 2021 at 4:04 PM Jason Szumlanski <<a href="mailto:jason@floridasolardesigngroup.com">jason@floridasolardesigngroup.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="auto">Someone reached out to me who had a PV system installed two years ago by another contractor on her shingle roof. Almost immediately it started having loud popping noises intermittently, but pretty consistently day to day. The homeowner thought it sounded like expansion and contraction. That made sense, so the original contractor came back multiple times to tighten things up. The problem never went away and lasted about 6 months until it was driving her crazy and she had the panels only removed. The sounds stopped. Legal proceedings ensued. Everything was dropped and she now has rails up, panels in garage, and no clamps.<div dir="auto"><br></div><div dir="auto">The panels have been in her garage for 18 months. I went to inspect today. She has Quickmount LMount flashings, Ironridge XR100 rails and had UFOs. The UFOs were tightened so much that they were tearing the t-bolts out of the top channel of the rail. I don't know if that was from the original installation or after they came back to try to resolve the issue. The UFOs had also dug in pretty deeply to the top of the module frames. None of the glass was broken.</div><div dir="auto"><br></div><div dir="auto">I could not find much evidence of module frames slipping on the rails and causing marks. The flashings and L-feet are all properly installed in trusses at 48 or 24-in centers. The square bolts securing the L-feet to rails are all tight and show no evidence of slippage. The attic looks great. 5/8 ply over manufactured trusses (southern pine). It's a Gable roof with about 20 feet eave to ridge. Again, everything looks great in the attic.</div><div dir="auto"><br></div><div dir="auto">There are two rows of panels. I thought maybe the two rows were rubbing on each other. But I could not find any evidence on the short sides of the modules that would suggest this was the problem.</div><div dir="auto"><br></div><div dir="auto">Has anyone seen this issue before? I'm thinking about putting a few test panels back up with standard mid clamps rather than UFOs just to see if that changes anything. </div><div dir="auto"><br></div><div dir="auto">Jason Szumlanski</div><div dir="auto">Florida Solar Design Group</div></div>
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