Back in the early 1980s I ventured around Southern California looking for old boiler plants to photograph. A tall smoke stack above the horizon made them easy to find.
This Boiler Plant building is at the Pasadena City College, built in 1924, along with its monolithic concrete smoke stack. This Boiler Plant provided Steam Heat to buildings on campus.
Two Boilers inside the Plant are 250 HP each. The Llewellyn Iron Works boiler (near) and an Erie City Iron Works boiler (far) are fired by clean burning natural gas, and operate at almost 70lbs steam pressure.
Here is Ron Jackson, the Plant Engineer making an adjustment of a steam valve affecting the speed of the American Marsh Vacuum Pump (size 8x12x16) that is located in a pit inside the boiler room. This pump is set at the lowest point of the heating system to pull a vacuum on condensate return line, this in turn making the heating system more efficient. In the background is a boiler feed, Duplex Steam Pump (8x5x10) also manufactured by American Marsh.
Here is another view of the of the Steam Vacuum Pump. Warm condensation can be seen leaking from the packing gland, this in turn keeps the Primordial Life Form growing. (white area on the pump) Maybe this is how life survived a half billion years ago on earth, by living around a geothermal steam vent.