Inter-Bp Units Heating Heat Exchanger Isothermal Control - Daikin FTX25JVEA9 Service Manual

Si18-201
3.34 Inter-BP Units Heating Heat Exchanger Isothermal
Control
Purpose of the This function ensures appropriate refrigerant distribution to each BP unit in heating operation.
Function It prevents abnormal increase of the high pressure and operation with gas shortage due to
uneven refrigerant distribution (Protection function).
Outline The indoor unit heat exchanger thermistors (of all connected room units including non-operating
room units) in heating operation are detected. Then, the highest heat exchanger temperature
DCMXT is compared with the heat exchanger temperature of each room unit. If the temperature
difference exceeds the predetermined value, it is judged that that indoor unit heat exchanger
thermistor position in subcooled zone, and the motorized valves of room units with the
temperature difference exceeding the predetermined level is opened to return to the saturation
zone.
Details The maximum value of DCMXT of BP units is compared with DCMXT of each room. If the
temperature difference exceeds DCABC (10°C), open the motorized valve of that BP unit.
Main Functions
System control
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