- 13 50 00 - SPECIAL INSTRUMENTATION
- 13400 - Measurement and Control Instrumentation
- 13430 - Boxes, Panels, and Control Centers
- 13440 - Indicators, Recorders, And Controllers
- 13500 - Recording Instrumentation
- 15500 - Heat Generation
- 15510 - Heating Boilers and Accessories
- 15700 - Heating, Ventilating, Air Conditioning Equipment
- 15710 - Heat Exchangers
- 15760 - Terminal Heating and Cooling Units
- 15770 - Floor-Heating & Snow-Melting Equipment
- 23 50 00 - CENTRAL HEATING EQUIPMENT
- 23 52 00 - Heating Boilers
- 23 52 16 - Condensing Boilers
- 23 52 19 - Pulse Combustion Boilers
- 23 52 23 - Cast-Iron Boilers
- 23 52 33 - Water-Tube Boilers
- 23 52 39 - Fire-Tube Boilers
- 23 57 00 - Heat Exchangers for HVAC
- 23 57 16 - Steam-to-Water Heat Exchangers
- 23 57 19 - Liquid-to-Liquid Heat Exchangers
- 23 60 00 - CENTRAL COOLING EQUIPMENT
- 23 70 00 - CENTRAL HVAC EQUIPMENT
- 23 80 00 - DECENTRALIZED HVAC EQUIPMENT
- 23 82 00 - Convection Heating and Cooling Units
- 23 82 16 - Air Coils
- 23 82 19 - Fan Coil Units
- 23 82 23 - Unit Ventilators
- 23 82 26 - Induction Units
- 23 82 33 - Convectors
- 23 82 36 - Finned-Tube Radiation Heaters
- 23 82 39 - Unit Heaters
- 23 83 00 - Radiant Heating Units
- 40 90 00 - INSTRUMENTATION AND CONTROL FOR PROCESS SYSTEMS
- 40 91 00 - Primary Process Measurement Devices
- 40 93 13 - Analog Controllers
- 40 93 23 - Chart Recorders
- 40 94 00 - Digital Process Controllers
- 40 95 13 - Process Control Panels and Hardware
- 40 95 73 - Process Control Wiring
- 40 97 00 - Process Control Auxiliary Devices
- 40 97 10 - Process Control Annunciators