El Cajon (Calif.) Plumbing & Heating Supply has come a long way from its origins back in Penns Grove, N.J. Owner Shelly Hirshman Olsher’s parents opened a plumbing supply store in Penns Grove after World War I. Her parents moved to Southern California in 1973 and established El Cajon Plumbing & Heating Supply and The Bath Gallery, its designer showroom.