Panasonic Urban Multi MX1R Series Service Manual

Function PACD011001C2246 Function Urban Multi “MX1R, ME1R Series” Using R-407C1.7 Oil Return Operation1.7.1 MX1R SeriesIn order to collect refrigeration oil held up in connecting piping, the compressor's operating time is counted,and oil return operation is carried out for 4 minutes every 8 hours (2 hour after turning on the power supply,and every 8 hours after that).(When heating, the indoor unit's electric heater is tuned off one minute prior to oil return operation inpreparation for oil return.)(1) Compressor Operation Frequency*When heating, frequency is lower than that given in the table for the first 30 seconds and 30 seconds aftercompletion.*Frequency may drop according to the various types of step-down control. If so, the next oil return must becarried out 4 hours later.(2) Opening of the electronic expansion valve(3) 4-way changeover valve (Y1R)When cooling: No changeWhen heating: Switches to cooling mode(4) Fan and solenoid valveStep No. changes according to high pressure.(Step No. becomes higher as high pressure decreases.)c→d30 sec. after oil return start or high pressure is less than 16kg/cm2 (1.57MPa)d→eHigh pressure is less than 8 kg/cm 2 (0.78MPa)e→dHigh pressure is greater than 16.4 kg/cm 2 (1.61MPa)d→cHigh pressure is greater than 22 kg/cm 2 (2.16MPa)∗When heating only*On when low pressure <0.3 kg/cm 2 (0.029MPa)Off when low pressure <0.8 kg/cm 2 (0.078MPa)Notes)1. While the oil return timer is counting, if the compressor frequency continues at 68Hz (38Hz + ON for 8,10HP) or more for more than eight minutes with defrosting, the timer is reset and counts again for eighthours.2. If on standby (forced thermostat OFF) or the compressor stops due to malfunction during oil returnoperation, the next time the compressor starts, oil return operation is again carried out for four minutesafter completion of soft start.3. Oil return operation is not carried out for 28 minutes after defrost is completed.Type Cool HeatCU-5(5HP) 106Hz 96HzCU-8(8HP) 106Hz+ON 86Hz+ONCU-10(10HP)106Hz+ON 86Hz+ONOutdoor unit Operating indoor unit Indoor unit turned offWhen cooling 2000 pulses (fully open) 2000 pulses (fully open) 1440 pulsesWhen heating 2000 pulses (fully open) 2000 pulses (fully open) 2000 pulses (fully open)Step No. Y2S Y3S,Y4S Fanc ON∗ ON H(H+ON)d OFF* ON L(H+OFF)e OFF* ON OFF