2024-390-E-AMS-Brady Services-WCOB Server Room HVAC

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Orange County West Campus Office Building -HVAC PDC Project 23020 In-Row Computer Room Air Conditioners 23 81 24.01 - 7 3.10 COMPRESSOR SHORT CYCLE CONTROL A.To help maximize the life of the compressor,there shall be start-to-next start delay for the compressor.The control shall monitor the number of compressor starts in an hour.If the compressor starts more than 10 times in 60 minutes,the local display and remote monitoring shall notify the user through a Compressor 1 Short Cycle event. 3.11 CONDENSER CONTROL A.Units may be matched to a premium efficiency condenser control with enhanced monitoring, alarming,and diagnostics.The condenser control shall have an automated,low-noise mode and fan reversal for cleaning mode. 3.12 SYSTEM AUTO RESTART A.The auto restart feature shall automatically restart the system after a power failure.Time delay shall be programmable. 3.13 SEQUENTIAL LOAD ACTIVATION A.On initial startup or restart after power failure,each operational load shall be sequenced with a minimum delay of one second to minimize total inrush current. 3.14 LOW-PRESSURE MONITORING A.Units shall ship standard with low-pressure transducers for monitoring compressor suction pressure.If the pressure falls due to loss of charge or other mechanical cause,the corresponding circuit shall shut down to prevent equipment damage.The user shall be notified of the low- pressure condition through the local display and remote monitoring 3.15 WINTER START TIME DELAY-AIR-COOLED MODELS A.An adjustable software timer shall be provided to assist with compressor starting during cold weather.When the compressor starts,the low-pressure input shall be ignored for the period set in the user-adjustable timer.Once the time period has elapsed after the compressor start,the low- pressure input should remain in the normal state.If the low-pressure input does not remain in the normal state when the time delay has elapsed,the circuit shall lock out on low pressure.The low- pressure alarm shall be announced on the local display and communicated to remote monitoring systems. 3.16 REFRIGERANT PRESSURE TRANSDUCER FAILURE A.The control shall monitor the high-side and low-side refrigerant pressure transducers.If the control senses the transducer has failed,has been disconnected,has shorted or the reading has gone out of range,the user shall be notified through an event on the local display and remote monitoring. The corresponding circuit that the failure has occurred on shall be disabled to prevent unit damage. 3.17 OIL RETURN PROTECTION A.The control shall monitor compressor operation and staging to ensure that liquid and hot gas velocity are maintained for proper oil return to the compressor. 3.18 DIGITAL SCROLL HIGH-TEMPERATURE PROTECTION A.The control shall monitor digital scroll temperature during unit operation.A compressor temperature limit shall be imposed to help prevent damage to the compressor.If the temperature reaches the maximum temperature limit,the compressor shall be locked out and an alarm shall be annunciated on the local display and through monitoring.After the initial lockout,the control shall continue to monitor compressor temperature during the off-cycle and re enable the circuit once a safe operating temperature is reached.The control shall store the number of high temperature trips.The number of trips shall be accessible through the local display. 3.19 DIGITAL SCROLL SENSOR FAILURE A.The control shall monitor the status of the digital scroll sensor.If the control senses that the thermistor is disconnected,shorted or the reading goes out of range,the user shall be notified through an event on the local display and remote monitoring. Docusign Envelope ID: 8DED1454-68D2-4E36-9FC6-E56FF2124E5D