17SYSTEM SAFETIES3 Minute Time DelayIn order to protect the compressor, there is a 3 minute delay onbreak even if the control is calling for heating or cooling. Thecompressor will have an additional 1 minute delay when poweringthe unit on for the first time, or after a power failure.Compressor Top Temperature ProtectionThe unit will stop working when the compressor top temperatureprotector cuts off, and will restart after the compressor toptemperature protector restarts.Compressor Discharge Temperature ProtectionWhen the compressor discharge temperature reaches a higher onethan in normal operation, the running frequency will be limitedbased on the algorithm presented below:— If the compressor discharge temperature is lower than194_F (90_C), there is no limit in the frequency.— If this value is between 194_F and 221_F(90_C), the compressor will continue runningat the current frequency.— If this value is now between 221_F and 239_F(105_C), the frequency will decrease to a lowerlevel every 3 minutes.— When the compressor discharge temperature reaches avalue higher than 239_F (115_C), and has been runningat this condition for 5 seconds, the compressor stops.Fan Speed ProtectionWhen the indoor fan speed has been too low (300RPM) for certaintime, the unit will stop and the LED will display the failure.Inverter Module ProtectionThe Inverter module is protected for abnormalities in current,voltage and temperature. If abnormal values of any of these takeplace, the corresponding code will be displayed in the indoor unitand the unit will stop.Indoor Fan Delayed OperationWhen the unit starts up, the louver will be active immediately andthe indoor fan will operate 10s later. If the operating mode isheating, the indoor fan will also be controlled by the anti--coldblow function.Compressor Preheating FunctionThe compressor crankcase heater will activate if:— The outdoor ambient temperature, T4, is lower than37_F (3_C) and power has been recently supplied to themachine.— If T4 < 37_F (3_C) and the compressor has not beenoperating for over 3 hours.During the preheating mode, a weak current flow flows throughthe compressor coil from the wiring terminal of the compressor.The compressor is heated when this is not operating.The preheating function will deactivate If T4 is greater than 41_F(5_C) or the compressor starts operating.Zero Crossing Detection Error ProtectionIf the a detected zero crossing time interval is not correct for acontinuous 240 seconds, the unit will stop and the LED willdisplay the failure. The correct zero crossing signal time intervalshould be between 6 to 13 minutes.Condenser temperature protectionThe condenser temperature protection function acts as follows:— If the condenser coil temperature (T3) is between 131_Fand 140_F (55C__C), the compressor frequencywill decrease to a lower level until it reaches the lowestvalue, F1. It then runs at this F1 frequency. OnceT3<129_F (54_C), the compressor will continue runningat the current frequency.— When the coil temperature reaches a value lower than126_F (52_C), the compressor will not limit thefrequency and resumes to the required frequency.— If T3>140_F (60_C) for 5 seconds, the compressor willstop and restart once the coil temperature reaches a valuelower than 126_F (52_C).Evaporator Temperature ProtectionThe evaporator temperature protection function acts as follows:— If the evaporator coil temperature (T2) is lower than32_F (0_C), the compressor will stop and restarts onceT2 ≥ 41_F (5_C).— If 32_F ≤ T2 <39_F (0_C ≤T2 <4_C), the compressorfrequency will be limited and decreased to a lower level.— Now, if 39_F ≤T2 <45_F (4_C ≤T2 <7_C), thecompressor continue running at the current frequency.— If T2>45_F (7_C), the compressor frequency will not belimited, and operation is normal.SEQUENCE OF OPERATIONInterfaceA wireless remote control, supplied with the unit, is the interfacebetween the fan coil and the user. The wireless remote control hasthe following characteristics:S Capable of displaying _C and _F with _F being the defaultsetting. To change the default setting, refer to the Owner’sManual.S The remote control setpoint range is from 62_F (17_C) to86_F (30_C) in increments of 1_F (1_C).S The wireless remote control has an operating range of 25 ft.(7.62 m).S The same remote control can be used to control more than oneunit.S If the remote control is lost, damaged, or the batteries areexhausted, the system can be operated by using the manualbutton (forced Auto) located under the front panel.Manual ButtonAUTO/COOLA14359Fig. 16 – Manual Button Location on Unit
