Daikin FTX09NMVJU Service Manual

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Contents

Daikin FTX09NMVJU Service Manual Manual pdf 62 page image

Control Specification SiUS091601E51 Functions and Control3.11.1 Fully Closing with Power ONThe electronic expansion valve is initialized when turning on the power. The opening position is setand the pressure is equalized.3.11.2 Pressure Equalizing ControlWhen the compressor is stopped, the pressure equalizing control is activated. The electronicexpansion valve opens and the pressure is equalized.3.11.3 Opening Limit ControlThe maximum and minimum opening of the electronic expansion valve are limited.The electronic expansion valve is fully closed when cooling operation stops, and is opened at afixed degree during defrosting.3.11.4 Starting Operation ControlThe electronic expansion valve opening is controlled when the operation starts, thus preventing thesuperheating or liquid compression.3.11.5 Control when the frequency changesWhen the target discharge pipe temperature control is active, if the target frequency changes to aspecified value in a certain time period, the target discharge pipe temperature control is canceledand the target opening of the electronic expansion valve is changed according to the frequencyshift.3.11.6 High Discharge Pipe Temperature ControlWhen the compressor is operating, if the discharge pipe temperature exceeds a certain value, theelectronic expansion valve opens and the refrigerant runs to the low pressure side. This procedurelowers the discharge pipe temperature.3.11.7 Discharge Pipe Thermistor Disconnection ControlOutline The disconnection of the discharge pipe thermistor is detected by comparing the discharge pipetemperature with the condensation temperature. If the discharge pipe thermistor is disconnected,the electronic expansion valve opens according to the outdoor temperature and the operationfrequency, operates for a specified time, and then stops.After 3 minutes, the operation restarts and checks if the discharge pipe thermistor is disconnected.If the discharge pipe thermistor is disconnected, the system stops after operating for a specifiedtime.If the disconnection is detected repeatedly, the system is shut down. When the compressor runs for60 minutes without any error, the error counter is reset.Detail Determining thermistor disconnectionWhen the starting control finishes, the detection timer for disconnection of the discharge pipethermistor (A seconds) starts. When the timer is over, the following adjustment is made.1. When the operation mode is coolingWhen the following condition is fulfilled, the discharge pipe thermistor disconnection isascertained.Discharge pipe temperature +6°C (+10.8°F) < outdoor heat exchanger temperature09/12 class 15 classMaximum opening (pulse) 470 480Minimum opening (pulse) 32 52