Carrier 50EN 415 Installation, Operation And Maintenance Instructions

2011 - SAFETY ELEMENTSHigh pressure pressostatConnected to the compressor discharge, it will stop its operationwhen the pressure at that point reaches the setpoint. Itdisconnects at 42 bar and it is automatically reactivated.Low pressure pressostatWhen connected to the compressor suction, it will stop itsoperation when the pressure at that point goes down below thetare value (caused by obstructions in the circuit, excessive dirtin the filters, fan stop or ice formation in the evaporator).This pressostat disconnects at 2 bar and is automaticallyreactivated.Magnetothermals for line protectionThey are located at the beginning of the power lines for thecompressors and motor fan(s) to protect them.Automatic switch in the control circuitMagnetothermal switch that protects the operation circuit againstcontinuous surges as well as against high currents of shortduration (short circuits).Defrost controlThis safety device is intended to eliminate ice which couldaccumulate in the outdoor coil when the unit is working in theheating cycle. Defrosting is carried out by the control dependingon the value measured by the sensors on the outdoor coils andthe time set between defrosting operations.Main door switchBy using a mechanical device, it impedes access to the electricpanel when the unit is with voltage.Safety at the compressorTemperature probe for the discharge from the compressor toprotect the unit with discharge temperatures greater than 135ºC.Condensation and evaporation pressure controlThis safety device, integrated in the control, enables managingthe outdoor fans when the units are working in cooling mode withlow outdoor temperatures (condensation control) or in heatingmode with high outdoor temperatures (evaporation control). Thisaids the unit’s operation in all the seasons.In the case of EC electronic fans, such as those that are found inthese units by default, speed control will be proportional basedon the average pressure measured by the pressure transducersin the outdoor coils.Smoke detector (optional)In accordance with standard NF S 61-961, this smoke detectionstation uses a LED to indicate the installation status, and if theprobe detects the presence of smoke in the installation, it stopsthe operation of the unit.The station is installed in the factory in the main electric panelor in the auxiliary electric panel (depending on the model). Theprobe is placed on a pillar next to the supply fans.Anti-fire safetyThe electronic control can activate an anti-fire safety device thatdetains the unit when the return air surpasses a temperatureof 60°C (by default).It cannot return to operation until the temperature has droppedto below 40ºC.Smoke detecting station Smoke detecting probeAir inlet tubeControl of air flow- The supply plug-fans (standard) adapt their speed to theaverage flow measured by the differential pressure sensorand the value set as a setpoint in the electronic control.- For those units with centrifugal supply fans (optional), adifferential pressostat can be incorporated in order to measurethe variation in air flow. This pressostat allows the detection offan belt breakages, since the fan relay only detects operatingfaults that have arisen in the motor. This pressostat is installedin the factory in the main electric panel or in the auxiliaryelectric panel (depending on the model). This safety deviceis mandatory for units with electrical heaters and with gasburners if the unit does not have the supply plug-fans.