# Operazioni Code Description
61 MG Gas engine (internal combustion)
62 FA Direct fired heater
63 FE Cabin furnace
64 FF Special furnace
65 FG Water-tube boiler, fire-tube boiler, drum boiler
66 FJ Incinerator (including thermo disposal equipment and evaporating candles)
67 FL Economizer
68 FX Burner
69 FY Indirect fired heater
70 GD Water Boiler/Heater
71 HD Quench boiler/cooler
72 HE Recovery boiler
73 HS Water cooler
74 HT Super heater
75 HW Waste heat recovery unit
76 HM Electric exchanger (not sanitary)
77 HN Electric heating system applied to equipment
78 FR Glycol regenerator
79 VA Horizontal/Vertical pressure vessel (general)
80 VB Expansion tank, Pressurizer, Compensation tank, Expansion vessel, Damper