Mitsubishi Heavy Industries HMK60, Installation Manual

Page: 274 / 288

68
Disturbance in comfort
Alarm
nr.
Alarm text on the
display
Description May be due to
279 Sensor fault from heat
pump Sensor fault, hot gas in FDCW (Tho-D). ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Defective control board in FDCW
280 Sensor fault from heat
pump Sensor fault, suction gas in FDCW (Tho-S) ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Service valve closed
■ Defective control board in FDCW
281 Sensor fault from heat
pump Sensor fault, low pressure transmitter in FDCW. ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Service valve closed
■ Defective control board in FDCW
■
Fault in the refrigerant circuit
294 Incompatible heat pump Heat pump and indoor module do not work
properly together due to technical parameters. ■ Outdoor module and indoor module are not
compatible.
343 Low temp water out Low water out temperature during cooling or
tank defrost operation ■ Too low water fl ow
■ Too low return temperatur
347 Temp high press Temporary high pressure alarm ■ No/low water fl ow
■ Air in water system
403 Sensor fault from PCA
154 Sensor fault, Sensor incoming water in indoor
unit (BT3). ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Defective control board AA23 in indoor unit.
404 Sensor fault from PCA
154 Sensor fault, Sensor high pressure heating/
low pressure cooling in indoor unit (BP4). ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Defective control board AA23 in indoor unit.
412 Sensor fault from PCA
154 Sensor fault, Sensor outgoing water in indoor
unit (BT12). ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Defective control board AA23 in indoor unit.
415 Sensor fault from PCA
154 Sensor fault, Sensor fl uid pipe in indoor unit
(BT15). ■ Open circuit or short circuit on sensor input
■ Sensor does not work (see section
"Disturbances in comfort")
■ Defective control board AA23 in indoor unit.
418 Low temp water out Anti-freeze protection water heat exchanger
during defrost. ■ Too low water fl ow
419 Freeze prot. exch. defr. Anti-freeze protection water heat exchanger
during defrost. ■ Too low water return temperature