Four Parker Boiler Co. model G1536RL low NOXWater Wall boilers are part of a multiple-boiler replacement job at a California aerospace plant. Designed to ease service, the units incorporate Parker's low NOXSystem 4 with a cylindrical premix metal-fiber burner and a variable-frequency drive blower for additional energy savings.

Last year, Parker Boiler, Commerce, Calif., installed Water Wall boilers in several locations, including John Wayne Airport, Whittier Police Department, Northrop Grumman, Moorpark College and Boeing Co.