If your rust (iron oxide) problem is a tough one, I have a great rust remover. Its called Naval Jelly and its pretty powerful stuff (contains phosphoric acid). Use rubber gloves, and in the case of a thin layer of rust, you could dilute it with water. It will attack paint and probably anodized Al frames as well.
Undiluted, the stuff is a gel so it can be applied to a sloping surface. The iron oxide gets converted to iron phosphate which is water soluble and washes off. The nice thing about Nava Jelly is it is non-abrasive and it removes the iron oxide via a chemical process. In other words it doesn't affect glass, which leads me to my next point. Over the past ten years there has been a series of manufacturing improvements to PV modules. Fairly recently, PV module manufacturers have been applying a very thin dielectric layer to the top surface of the tempered, low-iron glass. This anti-reflective (AR) layer is extremely thin and some cleaning solutions and mild abrasives will attack the layer. Even fingerprints can attack the layer. I suspect that Naval Jelly will attack the AR coating. I havent researched any of the cleaning agents that are on the market that are supposed to be used with PV modules, but I would be very cautious of using anything but a very mild detergent with PV modules with an AR coating. In the case of Tom DeBates situation, the modules probably dont have an AR coating and either naval Jelly or a mild abrasive (that doesnt scratch glass) should work. - Peter Peter T. Parrish, Ph.D., President California Solar Engineering, Inc. 820 Cynthia Ave., Los Angeles, CA 90065 CA Lic. 854779, NABCEP Cert. 031806-26 peter.parr...@calsolareng.com Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885 ________________________________________ From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Jason Szumlanski Sent: Thursday, December 30, 2010 9:38 AM To: RE-wrenches Subject: Re: [RE-wrenches] cleaning modules Yup soft scrub works great in my experience. Rinse well. Never had a problem. Although, never took a microscope to the glass surface after use Disclaimer Im not buying you a new panel in the event of damage! Jason Szumlanski Fafco Solar From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Kent Osterberg Sent: Thursday, December 30, 2010 12:27 PM To: RE-wrenches Subject: Re: [RE-wrenches] cleaning modules Tom, Textured glass would complicate matters, but I'd try ceramic stove top cleaner. The fine abrasive partials might be just the ticket. Kent Osterberg Blue Mountain Solar, Inc. Tom DeBates wrote: hello Wrenches, I recently purchased some used modules. Unfortunately, they were mounted near a railroad track and many have a film of rust on the front surface. I have tried a few products; Dawn, Simple Green, vinegar (5% acidity), and Krud Kutter to safely remove the rust. So far the vinegar seems to be best when considering cost, disposal ,etc. But it still takes a good amount of time and "elbow grease". Today I will try CLR. Has anyone else run into a similar situation? If so, what products and/or methods did you use to remove rust stains? Awhile back I had to remove some urethane caulk from the face of module and had to resort to a solvent-based chemical (acetone....yes, acetone) with disastrous results..... thanks, tom Tom DeBates Habi-Tek 524 Summit St. Geneva,IL. 60134 630-262-8193 fax 630-262-1343 ________________________________________ _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
