We have an interesting situation in the enclave of Pasadena, CA. (1) The Pasadena Building and Safety Department is requiring the use of rigid conduit (only) on any DC and AC runs for grid-tied PV systems. They specifically prohibit EMT, LFNC and LFMC. This requirement applies to any DC or AC runs on the roof, and it applies to any DC or AC runs on exterior walls.
They do not require the use of rigid conduit on A/C equipment, lighting or any other piece of equipment requiring exterior-mounted conduit conveying electrical power. (2) They also disallow a rigid conduit run anywhere on the exterior surface of a chimney. Where a conduit run on an exterior wall encounters a chimney, they require that the conduit run follow the line where the chimney meets the wall/roof. This means up the wall, along the roof and back down the wall. Although I think (1) is overkill, I will comply this once and engage the AHJ before the next job we have in this town; I have graver reservations about (2). I have lived over 50 years in California and I have seen the results severe earthquakes can have on residential chimneys. If the chimney goes, the first place it happens is on the unsupported portion above the roof. The next place the chimney fails is the higher portion, attached to the building frame. I think I can remember just one case where a chimney failed within 3 feet of the foundation, and in that case most of the rest of the structure failed. Consequently if a chimney fails, there will be hundreds of pounds of brick raining down on the rigid conduit where it runs along the chimney roof interface. I would argue that the safest place for a rigid conduit run would be around the chimney in the crawl space (if any) underneath the house, attached to floor joists. If that option is not available I would argue for a run around (and anchored to) the exterior chimney at about 2-3 feet above grade. Is item (2) essentially a B&S issue not addressed by the Fire Department? Has anyone encountered these sorts of requirements elsewhere? Comments? - Peter Peter T. Parrish, President California Solar Engineering, Inc. 820 Cynthia Ave., Los Angeles, CA 90065 Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885 CA Lic. 854779, NABCEP Cert. 031806-26 peter.parr...@calsolareng.com _______________________________________________ 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
