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ABCC P2 - Bldg 1 - 1-M0.22_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 Cooling or Heating will turn off immediately. The fan will then turn off in 30 to 60 seconds. Typically, thereafter, the supply fan will cycle on a call for Heating, Cooling, or Dehumidification. HVAC Source Configuration Options HVAC source will determine the mode of operation (Heating or Cooling Mode) of the unit. Return 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 Uses Unoccupied Setback Offset Setpoints for Heating and Cooling calls. The outdoor air damper will be closed except if the unit is in Unoccupied Economizer Free Cooling Mode. If there is no call for Heating or Cooling, 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. Unoccupied Cooling operation is enabled when the space Temperature rises above the Cooling Mode Enable Setpoint plus The unoccupied cooling offset. Mechanical cooling is disabled if the outdoor air temperature falls 1°F below the Cooling Lockout Setpoint and will remain disabled until the outdoor air temperature rises 1°F above the Cooling Lockout Setpoint. If the outdoor air temperature disables mechanical cooling while it is currently operating, mechanical cooling will stage off as minimum run times and stage down delays are satisfied. If the economizer is enabled, it will function as the first stage of Cooling. 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. Economizer Operation (Standard) During Heat and Vent Modes, the economizer will remain at its minimum position. During Unoccupied Mode, the economizer can be used for night setback free cooling; otherwise it will remain closed. Comparative Enthalpy Economizer Operation If the outdoor enthalpy is below the Comparative Economizer Enable Setpoint by the comparative economizer enable deadband amount, and the outdoor enthalpy is less than the return air enthalpy 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, or if the outdoor air enthalpy rises above the return air enthalpy by the comparative economizer enable deadband amount, then economizer operation will be disabled. Dehumidification Mode The Dehumidification Mode is initiated when the indoor humidity rises above the Indoor Humidity High Reset Source Setpoint. The unit will leave the Dehumidification Mode when the humidity falls below the Indoor Humidity Low Reset Source Setpoint. Occupied and Unoccupied: Dehumidification can be initiated anytime in the Occupied or Unoccupied Mode during Cooling, Heating. This can create a Cooling Dehumidification Mode, a Heating Dehumidification Mode, or a Vent Dehumidification Mode. Any calls for Unoccupied Dehumidification use the same Dehumidification Setpoint as during the Occupied 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. During Dehumidification, the economizer will be held to its minimum position. Dehumidification will require the use of an Outdoor and Indoor Humidity Sensor. 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. Unoccupied Heating operation is enabled when the space temperature falls below the Heating Mode Enable Setpoint minus the unoccupied heating offset. 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). Mechanical heating is disabled if the outdoor air temperature rises 1°F above the Heating Lockout Setpoint and will remain disabled until the outside air temperture falls 1°F below the Heating Lockout Setpoint. If the outside air temperture disables mechanical heating while it is currently operating, mechanical heating will stage off as minimum run times and stage down delays are satisfied. 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. Space Air Temperature Control of High Percentage Outdoor Air Units During this space control operation, if the configured minimum outdoor air damper (economizer) position is less than 100%, the economizer can open farther for free cooling. If both the space temperature and the space humidity are satisfied, the outdoor air temperature HVAC Setpoints to determine if a continued demand for heating or cooling is required to prevent dumping. If the outdoor air temperature is greater than the HVAC Cooling Setpoint or less than the HVAC Heating Setpoint, plus the Occupied deadband, the unit Controller will continue mechanical cooling or heating operation and stage or modulate it as necessary to maintain the Vent Mode Supply Air Setpoint (calculated to be halfway between the Space Heating and Cooling Mode Enable Setpoints). While the unit is under outdoor air temperature control, Dehumidification Mode is then initiated based on an Outdoor Air Dewpoint Setpoint with reheat controlling to the Supply Air Setpoint. Any call for space Cooling, Heating, or Dehumidification will cancel the outdoor operation and return the unit to space control. OCCUPIED COOLING : 72˚F OCCUPIED HEATING : 70˚F UNOCCUPIED COOLING : 78˚F UNOCCUPIED HEATING : 65˚F 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. Space Temperature Sensor Failure Alarm If the Space Sensor is configured as the controlling sensor (Mode Enable Sensor) or as the reset sensor, and if the controller detects an open or short circuit on the space sensor input, or if the controller detects a missing E-BUS Digital Space Sensor, then a Space Temperature Sensor failure alarm is generated. If the Space Sensor is configured as the controlling sensor and the failure alarm is generated, the unit will shut down. If the Space Sensor is only configured as a reset sensor and the failure alarm is generated, the space temperature will default to a value half way between the Heating and Cooling Mode Enable Setpoints, and the unit will continue to run. 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. Return Air Sensor Failure Alarm This alarm is generated if the controller is configured to have a Return Air sensor, but does not detect it. 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: RTU-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-M0.22PHASE 2 -MAIN CLUBHOUSE MECHANICALSEQUENCE OF OPERATION2022-352 Author