ESIE15-08B | Part 2. Troubleshooting 2. Error code based troubleshootingPage 22 19/07/16Daikin Altherma Monobloc CA2.5. “A1-00” – Zero cross detection problem2.6. “A1-01” – Hydro PCB A1P abnormality2.7. “A5-00” – Freeze-up prevention (refrigerant)Trigger Effect ResetMultiple zero-cross is detected in approxi-mately 10 continuous seconds.Unit will stop operating. Manual reset via user interface.Possible cause Check Corrective actionFaulty wiring to hydro PCB A1P. Check wiring to PCB A1P. Adjust wiring when required.Faulty hydro PCB A1P. Check if the alive led is blinking in regularintervals.Check if the correct spare part is installed.Check if hydro PCB A1P receives power.Adjust the power to the PCB.Replace hydro PCB A1P when alive led isnot blinking in regular intervals.Adjust software of hydro PCB A1P orinstall correct spare part when required.Faulty or disturbance of the power supply.(Imbalance > 10%) Power drop.Short circuit.Check if the power supply is conform withregulations. No fluctuations in frequency.Adjust power supply when required.Power reset via outdoor unit.Trigger Effect ResetHydro PCB A1P detects EEPROM isabnormal.Unit will stop operating. Via power reset + via user interface.Possible cause Check Corrective actionFaulty hydro PCB A1P. Check if the alive led is blinking in regularintervals.Check if the correct spare part is installed.Check if hydro PCB A1P receives power.Adjust the power to the PCB.Replace hydro PCB A1P when alive led isnot blinking in regular intervals.Adjust software of hydro PCB A1P orinstall correct spare part when required.Trigger Effect ResetHeat exchanger thermistor measurestemperature below 0°C, 15 times in 300min.Unit will stop. Manual reset via user interface.Condensing temperature reaches a tem-perature of 59,5°C, 15 times in 300 min.Possible cause Check Corrective actionRefrigerant circuit is clogged. Check for possible blockage (blockagecan be checked by measuring the refriger-ant/pipe temperature. Sudden drop intemperature could indicate a blockage(Remark: this is not valid for the expan-sion valve)).Replace the blocked part.Faulty expansion valve. Check expansion valve (see page 97). Replace expansion valve when required(see page 131).Faulty outdoor unit thermistor. Check outdoor unit thermistors (seepage 88).Replace outdoor unit thermistor whenrequired (see page 124).Water pressure is too low Check the water pressure on the pressuregauge.Increase water pressure till ~2 bar. Referto the Installer Reference Guide.Check for possible water leaks.
