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ABCC P2 - Bldg 1 - 1-M0.23_1Supply Fan Operation Any time the supply fan is requested to start, a one-minute minimum off timer must be satisfied. If the timer is satisfied, the supply fan relay is activated while all other outputs are held off until their minimum off timers have been met. Upon going into the Occupied Mode or upon power-up, the controller will initiate a user-adjustable fan starting delay to provide a staggered start for systems with several HVAC units. To protect the dampers on MUA systems on startup, dampers open then the fan starts after the fan starting delay setpoint time expires. On shut down, the fan turns off first. The dampers close after the fan starting delay setpoint time expires or fan proving is deactivated. In Fan Cycle Mode or when going Unoccupied, the supply fan is held on for 10 seconds after Cooling has staged off or after Leaving Vent Mode and 90 seconds after the Heating has staged off. Occupied Mode The supply fan shall be configured to run continuously. Unoccupied Mode Upon going Unoccupied, the fan will turn off immediately. HVAC Source Configuration Options HVAC source will determine the mode of operation (Heating or Cooling Mode) of the unit. Outdoor Air Temperature. Occupied/Unoccupied Mode of Operation Internal Week Schedule An internal week schedule, which supports up to two start/stop events per day and allows scheduling of up to 14 holiday periods per year is available for determining occupied and unoccupied schedules. It also allows for daylight saving configuration. Unoccupied Operation The outdoor air damper will be closed and the unit will be off. HVAC Modes of Operation The HVAC Modes of Operation are as follows: •Cooling Mode •Heating Mode •Dehumidification Mode •Off Mode Cooling Mode Occupied Cooling is enabled when the temperature at the Mode Enable Sensor rises one deadband above the Cooling Setpoint. Cooling is disabled when the mode enable temperature falls one deadband below the Cooling Setpoint. The setpoint and deadband are user-adjustable. During Cooling Mode, Cooling Capacity shall be adjusted to maintain Discharge Air Temperature Setpoint. Dehumidification Mode shall take priority over Cooling Mode. Cooling with the Refrigerant System Modules In Cooling Mode, as the supply air temperture rises above the active Cooling Supply Air Temperture Setpoint, the compressors will stage on and modulate to maintain the active Supply Air Cooling Setpoint. Each RSM will independently control its compressors to achieve the most efficient cooling control. Each stage must meet its minimum off time (adjustable) before it is allowed to energize. Successive stages are subject to a cooling stage-up delay (adjustable). Cooling stages will continue to run until the supply air temperture falls below the active Supply Air Temperature Setpoint minus the cooling stage control window and the Cooling will begin to stage off. Each stage must meet its minimum run time (adjustable) before it is allowed to stage off. Successive stages are subject to a cooling stage down delay (adjustable). See the appropriate RSM Technical Guide for a more detailed sequence of operation. Comparative Enthalpy Economizer Operation If the outdoor enthalpy is below the Comparative Economizer Enable Setpoint by the comparative economizer enable deadband amount, then economizer operation will be enabled to act as the first stage of Cooling. If the outdoor air enthalpy rises above the Comparative Economizer Enable Setpoint by the comparative economizer enable deadband amount, then economizer operation will be disabled. Dehumidification Mode The dehumidification is initiated when the outdoor air dewpoint rises above the Outdoor Air Dewpoint Setpoint by 2°F. The unit will leave the Dehumidification Mode when the humidity falls 2°F below this setpoint. The outdoor air dewpoint is calculated using the outdoor air temperature and the outdoor air humidity. Occupied: Dehumidification can be initiated anytime in the Occupied Mode during Cooling and Heating. This can create a Cooling Dehumidification Mode or a Heating Dehumidification Mode. Dehumidification Operation on Direct Expansion Compressor Units Any direct expansion unit doing dehumidification will utilize one or more RSMs. Each RSM will control the compressors, condensers, and electronic expansion valves (on Bitzer VFD compressor units) for one or two refrigeration circuits. Up to four RSMs may be used in controlling up to eight circuits. The RSMD is used for digital compressor units, including heat pumps. The RSMV is used for Bitzer VFD compressor units (non-heat pumps). The RSMV-HP is used for Bitzer VFD compressor units that are heat pumps. The RSMVC-P is used for Copeland VFD compressor units. In the Dehumidification Mode, the compressors are controlled to maintain the Suction (Saturation) Temperature Setpoint. Each RSM will independently control its compressors to achieve the most efficient dehumidification control. Reheat During Cooling Dehumidification, reheat is controlled to the active Cooling Supply Air Setpoint. During Heating Dehumidification, reheat is controlled to the active Heating Supply Air Setpoint. Heating Mode Occupied Heating is enabled when the temperature at the Mode Enable Sensor falls one deadband below the Heating Setpoint. Heating is disabled when the Mode Enable temperature raises one deadband above the Heating Setpoint. In the Heating Mode, as the supply air temperature falls below the active Supply Air Heating Setpoint, the heating will begin to stage on or to modulate. Each stage must meet its minimum off time (adjustable) before it is allowed to energize, and successive stages are subject to a heating stage up delay (adjustable). Heating stages will continue to run until the supply air temperature rises above the active Supply Air Temperature Setpoint plus the heating stage control window at which point the heating will begin to stage off. Each stage must meet its minimum run time (adjustable) before it is allowed to stage off, and successive stages are subject to a heating stage down delay (adjustable). Low Ambient Operation A low ambient relay can be configured. Whenever the outdoor air temperature falls below the Low Ambient Setpoint, this low ambient relay will energize. This operation occurs in both the Occupied and Unoccupied Modes of Operation. Make-up Air Operation Occupied Mode: The Cooling and Heating Mode Enable Setpoints in conjunction with the Outdoor Air Temperature Sensor to determine the mode of operation. The Outdoor Air Dewpoint setpoint will initiate the Dehumidification Mode. The outdoor air damper will be 100% open position. DEHUMIDIFICATION : 52˚F COOLING SUPPLY AIR TEMPERATURE (DB/WB) : 52˚F/51˚F HEATING SUPPLY AIR TEMPERATURE : 92˚F Sensor Failure Alarms Supply Air Temperature Sensor Failure Alarm The Supply Air Temperature Sensor failure alarm is generated when the controller detects an open or short circuit on the Supply Air Temperature Sensor input. Once the alarm is generated, the unit will be completely shut down. If a sensor is properly detected after the unit has alarmed, the alarm will be cleared and the unit will restart operations. Outdoor Air Temperature Sensor Failure Alarm The Outdoor Air Temperature Sensor failure alarm is generated when the controller detects an open or short circuit on the Outdoor air Temperature Sensor input. When this occurs, the outdoor air reading will be artificially set to the half point between the cooling and Heating Lockout Setpoints. This will allow cooling and heating to continue operating. For MUA systems, the Outdoor Air Temperature Sensor is the controlling sensor (Mode Enable Sensor). This alarm forces the MUA into Heating Mode. Airflow Alarms •Outdoor Airflow Sensor Alarm If the controller is configured to have any of the above airflow sensors, but the controller does not detect that the sensor is connected, then the applicable alarm will occur. If the sensor is properly detected after the unit has alarmed, the alarm will be cleared. Missing Expansion Module Alarm •Preheat-X Board Missing •EM1 Expansion Missing •RSM Modules #1 -#4 Missing •Reheat Board Missing •ModGas Board Missing •12 Relay Board Missing If the controller is configured to have any of the above expansion boards (Modules), but the controller does not detect that board, then the applicable alarm will occur. If the board is properly detected after the unit has alarmed, the alarm will be cleared. Mechanical Failure Alarms Mechanical Cooling Failure Fixed Stage Cooling: The mechanical cooling failure alarm is generated if the supply air temperature fails to drop 5ºF (within a user-adjustable time period) from the temperature the supply air was at when the cooling was activated and the supply air temperature is not within 5ºF of the setpoint. The alarm will be cleared when the supply air temperature drops the 5ºF and sets the failure timer back to zero. Variable Capacity Compressors (Utilizing RSMs):This alarm is not generated; instead, the user has to monitor the compressor module alarms for mechanical cooling issues. Mechanical Heating Failure The Mechanical Heating Failure alarm occurs when the staged heating fails to raise the supply air temperature to within 5ºF of the Supply Air Heating Setpoint within the Mechanical Fail Timeout. The Mechanical Fail Timeout is reset back to zero whenever the Supply Air rises at least 5ºF as it climbs. As long as the supply air temperature continues to rise at least 5ºF within the Mechanical Fail Timeout, and eventually gets to the desired Heating Setpoint, the alarm will be cleared. On PREHEAT-X, the Heat Mode Leaving Air Setpoint is used instead of Supply Air Heating Setpoint to determine the alarm. Supply Fan Proof of Flow Interlock Alarm A proof of flow switch provides a 24 VAC wet contact closure when the supply fan is operating. If this contact opens while the fan is being called to run, all heating and cooling is disabled, the outdoor air damper closes (if it is not configured for outdoor temperature control or space control with high percentage outdoor air), and a fan proving alarm is generated. Fan proving needs to be configured for this alarm to occur. There is a 30 second delay for this alarm. Dirty Filter Alarm A differential pressure switch is used to provide a 24 VAC wet contact closure to indicate a dirty filter status. A dirty filter alarm is then generated. Dirty filter needs to be configured for this alarm to occur. Emergency Shutdown Alarm A 24 VAC wet contact input is available to be used when a normally closed smoke Detector, Firestat, or other shutdown condition occurs. If this contact opens, it will initiate shutdown of the VCCX2 and will generate an alarm condition. If an Occupied relay is configured, it will remain energized. BACnet override commands are canceled if the emergency shutdown alarm is activated. Sequence of Operation: DOAU-1 DRAWN BY: PROJECT NO.: SCALE: REVISION NO.DATE DESCRIPTION THE INFORMATION SHOWN ON THESE DRAWINGS IS OWNED BY AND IS THE PROPERTY OF SHEPPHIRD ASSOCIATES, ARCHITECTS + ENGINEERS. NO PART THEREOF SHALL BE COPIED, ADAPTED, OR DISTRIBUTED TO OTHERS WITHOUT THE PRIOR WRITTEN CONSENT OF SHEPPHIRD ASSOCIATES, ARCHITECTS + ENGINEERS. COPYRIGHT © 2023 26560 AGOURA ROAD, SUITE 106 CALABASAS, CA 91302 310.670.9144 A S S O C I A T E S ARCHITECTS + ENGINEERS S H E P P H I R D will.s@shep-ae.com 1 12-02-22 SD PRICING 2 2-10-23 DD PRICING 3 9-07-23 PHASE 2 90% CD Atlantic Beach Country Club Phase 2 Construction Documents 1600 Selva Marina Drive Atlantic Beach, FL 32233 1/4" = 1'-0" 1-M0.23PHASE 2 -MAIN CLUBHOUSE MECHANICALSEQUENCE OF OPERATION2022-352 Author