For over 70 years, Raypak Raypak is a wholly owned subsidiary of Rheem Manufacturing and has been the world’s leading manufacturer of copper finned boilers and heaters. In 2000 Raypak’s primary manufacturing facility was relocated to a completely new 235,000 square foot building in Oxnard, California, its current headquarters. Raypak’s design goals are and have always been high quality, reliability and energy efficiency.