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DRAWN BY:CHECKED BY:REVISIONSSCAMPBELL@PDCENGINEERS.COMORANGE COUNTY SPORTPLEX HVACREPLACEMENTPOOL UNITCONTROLSM6.01BID/PERMIT SETORANGE COUNTYJAV SWCPDC 2302205/17/2024POOL UNIT SEQUENCE OF OPERATIONSSystem Startup 1. Power is turned on or the system is restarted 2. After a short initial delay to allow the sensors to stabilize, the blower starts and operates continuously3. Based on sensor feedback, the system shall begin or resume operation based on the sequence belowAirside Configuration1. The system continuously delivers the specified supply air volume to the natatorium2. The minimum exhaust air volume is set to meet the engineer's schedule.3. The minimum outdoor air volume is set to meet the engineer's schedule.Dehumidification Mode 1. The return air relative humidity is above the humidity setpoint2. Return air dewpoint is above dewpoint setpoint.3. The compressor enters the Compressor Start sequence4. If the system cannot maintain the relative humidity below setpoint, the second compressor circuit will start5. Compressor waste heat is rejected into a glycol fluid loop which feeds the reheat coils and the air conditioning air-cooled heat exchanger in parallel.6. The reheat coils are fully modulating (0-100%). The reheat output will modulate to maintain the space temperature at set point year-round. Reheat coils that are on off or only give heat from one circuit are not acceptable since they do not closely match the requirement of the space and cause swings in space conditions.Air Conditioning Mode1. The return air temperature is above the room temperature setpoint2. The compressor starts, if not already operating in Dehumidification Mode3. Excess compressor hot gas is diverted to a fluid-cooled heat exchanger. Up to 100% of compressor heat is rejected into the glycol fluid loop which is pumped outdoors to an outdoor air-cooled heat exchanger for 100% heat rejection at summer design ambient conditions4. 100% of compressor heat is rejected at the outdoor air-cooled heat exchanger on a summer design day. On off-peak days, the air reheat output will modulate to maintain the space temperature at the set point5. If the system cannot maintain the return air temperature setpoint, the second compressor will startSpace Heating Mode1. The return air temperature is below the room temperature setpoint2. The microprocessor space heating output signal (0-10 volts) is sent to the heating coil controller. The signal output will regulate based on the return air temperatureExhaust Air Heat Recovery Mode1. The minimum outdoor air damper and minimum exhaust fan(s) are tied to the system's occupancy schedule and will operate as programmed2. Once the outdoor air temperature falls below the heat recovery setpoint (65 °F by default; field-adjustable) the glycol pump shall circulate a glycol mixture between the exhaust air and the outdoor air heat recovery coils, recovering heat from the space condition exhaust air and using it to preheat the incoming outside airPool Water Heating Mode1. The return pool water temperature is below the pool water setpoint and the pool water flow switch or minimum temperature differential is satisfied. 2. If the compressor is already operating due to a Dehumidification or Air Conditioning demand, the fluid control valve will divert fluid to the Titanium pool water heat exchanger to modulate the heating of the pool water. Pool water heating that does not use a titanium pool water heater or modulation to match the demands of the pool are not acceptable. 3. If there is no pre-existing demand for the compressor to operate, the microprocessor sends a signal to the auxiliary pool water heater (remote by others) to operate. The compressor will not operate solely for a pool water heating demand unless specifically configured to do so at the controller. Aux Pool Heat contact will be closed with insufficient flow. In order to prevent the pool from overheating, it is recommended that a field-installed aquastat (provided by others) be installed in series with these wires.4. Field-installed pool water temperature sensor(s) are provided to enable the smart pool feature. This feature provides the ability to activate booster pool water pump(s) feeding the unit when pool water heating is in demand.Freeze Protection1. The supply air temperature falls below the freezestat setpoint2. Exhaust fan(s) are stopped and outdoor air damper(s) are fully closed3. When the freezestat alarm is tripped, it must be manually cleared by the operatorDrain Pan Float Switch / Water Sensor1. Controls Contractor shall provide float switch in drain pan and wire to fan shutdown.2. If the float switch is activated, send alarm to BAS front end. Float switch activation shall require a manual reset.SEQUENCE OF OPERATIONSA. GENERAL ZONING/SCHEDULING1. Each AHU is a zone that can be individually assigned an operation schedule or operate in conjunction with other zones as defined by the Owner. If an override button associated with the AHU is pushed during normally occupied times, no change in operation will occur. If an override button is pushed during normally unoccupied times, both the AHU and central heating and/or cooling plant will turn on and operate in the occupied mode for the programmed time duration (set for two hours).2. Scheduling a. Regular Scheduling: Each zone has regular, day-to-day schedule of occupied hours. The Owner shall be consulted during the Submittal phase to establish all schedules. b. The controls system shall use an Optimized Start/Stop algorithm to maximum energy efficiency and occupant comfort. The HVAC equipment in each zone will start early enough so that the space temperatures in the zone are at setpoint by the beginning of occupied hours. The start time shall be automatically adjusted with changes in outside air temperature and based on adaptive occupant behavior. c. Holidays: Holidays can be scheduled up to a year in advance. During scheduled holidays, the zones remain in unoccupied mode. Consult the Owner on holiday scheduling.d. Special Event Scheduling: Special events can be scheduled up to a year in advance during which a zone will operate in occupied mode regardless of the zone’s regular schedule or scheduled holidays. e. BAS Operator Overrides: The BAS operator can override the entire building either on or off at single points in the global control module’s software. B. POOL DEHUMIDIFICATION UNIT1. The pool dehumidification unit shall run according to its own packaged controls.2. The controls contractor shall provide data cabling and conduit as required to connect the pool dehumidification unit to the BAS through a BACnet interface. Controls Contractor shall pull in available points at provide graphics on BAS front end.3. In addition to the sequence noted above, the BAS shall monitor (or calculate) the following analog and digital input and outputs listed on the Drawings and display all points on a neatly configured graphic at the operator workstation.4. EXHAUST AIR AND OUTDOOR AIR HEAT RECOVERY (RUN AROUND LOOP)A. The glycol run around heat recovery loop captures energy from the energy rich exhaust air and transfers It to the incoming outdoor air stream. Tempering the cold incoming Outdoor Air prior to blending with the recirculated air provides condensation and freeze up protection. THE POINTS IN THE TABLE ABOVE FOR THE POOL DEHUMIDIFICATION UNIT SHALL BE MONITORED BY THE BUILDING AUTOMATION SYSTEM VIA BACNET AND DISPLAYED ON THE GRAPHICS AT THE OPERATOR WORKSTATION.CONTROL CONTRACTOR TO COORDINATE CONTROLS PROTOCOL WITH MECHANICAL CONTRACTOR PRIOR TO ORDERING (BACNET MS/TP, BACNET IP, OR BACNET OVER ETHERNET)PROVIDE DATA CABLING, INTERFACING CARD, AND CONDUIT AS REQUIRED TO PULL THESE POINTS FROM THE UNIT BACK TO THE BAS.POOL DEHUM. UNIT POINTS LISTPOINTPOINTTYPEACTIVE ALARM PRESENTDIAUX HEAT STAGES ACTIVEAICOMPRESSOR 1 STATUSDICOMPRESSOR 2 STATUSDICOMPRESSOR SYSTEM 1 ACTIVE FAULT CODE AICOMPRESSOR SYSTEM 2 ACTIVE FAULT CODE AIDEHUMIDIFICATION MODEDIEMERGENCY HEATDOEVAPORATOR BYPASS DAMPER POSITION AIEVAPORATOR DISCH AIR TEMPAIEVAPORATOR DISCH RELATIVE HUMIDITY AIEXHAUST AIRFLOW CFMAIEXHAUST FAN MOTOR STATUSDIFORCE NON-PURGE MODEDOFORCE OCCUPIED MODE (WRITABLE) DOFORCE PURGE MODEDOFORCE UNOCCUPIED MODEDOHEAT RECOVERY PUMP STATUSDIHEAT RECOVERY SETPOINTAOMODULATED HEATAIOCCUPIED STATUSDIOUTSIDE AIR DAMPER POSITIONAIOUTSIDE AIR RELATIVE HUMIDITYAIOUTSIDE AIR TEMPAIOUTSIDE AIRFLOW CFMAIPURGE AIRFLOW CFMAIPURGE FAN MOTOR STATUSDIPURGE MODE STATUSDIRECIRCULATION AIR DAMPER POSITION AIREHEAT LEVELAIRETURN AIR CO2 PPMAIRETURN AIR RELATIVE HUMIDITYAIRETURN AIR TEMPAISPACE AIR PRESSUREAISPACE AIR RELATIVE HUMIDITYAISPACE AIR TEMPAISPACE DEWPOINTCALCULATEDSUPPLY AIR TEMPAISUPPLY AIRFLOW CFMAISUPPLY FAN MOTOR STATUSDISURFACE COLD WALL TEMPAIUNIT STATUSDINUMBER DATE DESCRIPTION11/18/2024 <br />Docusign Envelope ID: D4F3B98E-0756-4A0C-A3AD-05AA32D39F1C