Carrier WeatherMaker 48A2020 Controls, Start-up, Operation, Service And Troubleshooting Instructions

108T210 (Building Pressure Transducer Failure)The building pressure transducer (PressuresAIR.PBP)fails if the signal from the 4 to 20 mA building pressure trans-ducer (used to control the power exhaust fans and the buildingpressure) is below 2 mA. If the alert occurs, then the economiz-er will be closed and the power exhaust fans turned off. Thisalert will automatically reset. Check the building pressuretransducer and sensor tubing. The sensor is located in the aux-iliary control box. The alert will automatically reset.T211 (Static Pressure Transducer Failure)The static pressure transducer (Pressures  AIR.P  SP)fails if the signal from the 4 to 20 mA static pressure transducer(used to control the VFD speed) is below 2 mA. This failurewill cause the unit to stop due to the potential damage thatcould occur due to over-pressurization. Check the pressuretransducer and sensor tubing. The sensor is located in the aux-iliary control box. The alert will automatically reset.T220 (Indoor Air Quality Sensor Failure)The indoor air quality sensor (InputsAIR.QIAQ) fails ifthe signal from the 4 to 20 mA sensor is below 2 mA. If the in-door air quality sensor fails, demand control ventilation is notpossible. The control defaults to the maximum vent position.Recovery is automatic. Reason for error is either a faulty sen-sor, wiring error, or damaged input on the MBB control board.T221 (Outdoor Air Quality Sensor Failure)The indoor air quality sensor (InputsAIR.QOAQ) fails ifthe signal from the 4 to 20 mA sensor is below 2 mA. If the out-door air quality sensor fails, OAQ defaults to 400 ppm and de-mand control ventilation will continue. Recovery is automatic.Reason for error is either a faulty sensor, wiring error, or dam-aged input on the CEM control board.T229 (Economizer Minimum Position Override Input Failure)If the unit is configured to use the remote position override forthe economizer and the input Econo Min. Pos. Override (Con-figurationIAQAQ.SPIQ.O.P) input 4 to 20 mA read-ing is less than 2 mA then an alert will occur and the default soft-ware minimum position will be used for the economizer. Thealert will automatically reset.T300 (Space Temperature Below Limit)If the space temperature is below the configurable SPT LowAlert Limits (occupied [ConfigurationALLMSP.L.O]for 5 minutes or unoccupied [Configuration  ALLM SP.L.U] for 10 minutes), then an alert will be broadcast. Thealert will automatically reset.T301 (Space Temperature Above Limit)If the space temperature is above the configurable SPT HighAlert Limits (occupied [ConfigurationALLMSP.H.O]for 5 minutes or unoccupied [Configuration  ALLM SP.H.U] for 10 minutes), then an alert will be broadcast. Thealert will automatically reset.T302 (Supply Temperature Below Limit)If the supply-air temperature measured by the supply tempera-ture sensor is below the configurable SAT LO Alert Limit/Occ(ConfigurationALLMSA.L.O) for 5 minutes or the SATLO Alert Limit/Unocc (Configuration  ALLM  SA.L.U)for 10 minutes, then an alert will be broadcast.T303 (Supply Temperature Above Limit)If the supply temperature is above the configurable SAT HIAlert Limit Occ (ConfigurationALLMSA.H.O) for 5minutes or the SAT HI Alert Limit/Unocc (Configuration ALLMSA.H.U) for 10 minutes, then an alert will be broad-cast. The alert will automatically reset.T304 (Return Air Temperature Below Limit)If the return-air temperature measured by the RAT sensor is be-low the configurable RAT LO Alert Limit/Occ (ConfigurationALLMRA.L.O) for 5 minutes or RAT LO Alert Limit/Un-occ (ConfigurationALLMRA.L.U) for 10 minutes, thenan alert will be broadcast.T305 (Return Air Temperature Above Limit)If the return-air temperature is below the RAT HI Alert Limit/Occ(ConfigurationALLMRA.H.O) for 5 minutes or RAT HIAlert Limit/Unocc (Configuration  ALLM  RA.H.U) for10 minutes, then an alert will be broadcast. The alert will automat-ically reset.T308 (Return Air Relative Humidity Below Limit)If the unit is configured to use a return air relative humiditysensor through the Return Air RH Sensor (ConfigurationUNITSENSRRH.S) setting, and the measured level isbelow the configurable RH Low Alert Limit (ConfigurationALLMR.RH.L) for 5 minutes, then the alert will occur.The unit will continue to run and the alert will automaticallyreset.T309 (Return Air Relative Humidity Above Limit)If the unit is configured to use a return air relative humiditysensor through the Return Air RH Sensor (Configuration UNITSENSRRH.S) setting, and the measured level isabove the configurable RH High Alert Limit (ConfigurationALLMR.RH.H) for 5 minutes, then the alert will occur.Unit will continue to run and the alert will automatically reset.T310 (Supply Duct Static Pressure Below Limit)If the unit is a VAV unit with a supply duct pressure sensor andthe measured supply duct static pressure (PressuresAIR.PSP) is below the configurable SP High Alert Limit (Config-urationALLMSP.L) for 5 minutes, then the alert willoccur. The unit will continue to run and the alert will automati-cally reset.T311 (Supply Duct Static Pressure Above Limit)If the unit is a VAV unit with a supply duct pressure sensor andthe measured supply duct static pressure (PressuresAIR.PSP) is above the configurable SP High Alert Limit (Config-urationALLMSP.H) for 5 minutes, then the alert willoccur. The unit will continue to run and the alert will automati-cally reset.T312 (Building Static Pressure Below Limit)If the unit is configured to use a VFD controlled power exhaustor a modulating power exhaust then a building static pressurelimit can be configured using the BP Low Alert Limit (Config-uration  ALLM  BP.L). If the measured pressure (Pres-suresAIR.PBP) is below the limit for 5 minutes thenthe alert will occur.T313 (Building Static Pressure Above Limit)If the unit is configured to use a VFD controlled power exhaustor a modulating power exhaust then a building static pressurelimit can be configured using the BP HI Alert Limit (Configu-ration  ALLM  BP.H). If the measured pressure (Pres-suresAIR.PBP) is above the limit for 5 minutes, thenthe alert will occur.T314 (IAQ Above Limit)If the unit is configured to use an CO 2 sensor and the level (In-puts  AIR.Q  IAQ) is above the configurable IAQ HighAlert Limit (Configuration  ALLM  IAQ.H) for 5 min-utes then the alert will occur. The unit will continue to run andthe alert will automatically reset.A404 (Fire Shutdown Emergency Mode)This alarm occurs when the fire shutdown input is active (ei-ther open or closed depending upon its configuration). If the