INDUCTION UNIT SYSTEM Induction unit systems are designed to heat and cool the perimeter area of a building up to about fifteen feet from the windows. The primary air fan forces air out of the jets in the induction unit, causing an induced flow of return air from the room, through the filter and coil. The room controller senses the return air at this point. The total volume discharging from the grills of the induction unit is the sum of the primary airflow to the unit and the induced airflow. The primary air is cold during winter mode and heated water is provided via the secondary loop to the control valve associated with each induction unit. The controller has the option of heating the return air or allowing it to pass unheated through the coil to be mixed with the cold primary air. The primary air is heated during summer mode, based on reset from the outside air temperature. The induction unit receives chilled water via the secondary water loop. Usually the water temperature is controlled to minimize condensation at the room level. Some systems work with chilled secondary water or heated secondary water all year with the heating or cooling source respectively being the primary air. These units do not require reversal of the control action regarding the induction unit controllers. These systems have the potential for great inefficiency. s/w 7.58 SUPPLY FAN RETURN FAN PRIMARY SUPPLY AIR COOLING HEATING COIL COIL MIXED AIR INDUCTION UNIT IN AN OFFICE VALVE CONTROL SUPPLY AIR TO OFFICE PUMP SECONDARY VALVE IN BOILER/CHILLER ROOM TT TT TT DM DM DM RETURN AIR EXHAUST AIR OUTDOOR AIR CWS/HWS CWR/HWR
RkJQdWJsaXNoZXIy ODY1ODQy