U0 Outdoor Unit: Gas Shortage Alert - Daikin RXYQ96PYDN Service Manual

Troubleshooting by Indication on the Remote Controller
U0
3.44 Outdoor Unit: Gas Shortage Alert
U0
Remote
Controller
Display
Applicable
RXYQ72P~240PYDN, PTJU
Models REYQ72P~240PYDN, PTJU
Method of Detect gas shortage based on the temperature difference between low pressure or suction pipe
Malfunction and heat exchanger.
Detection
Malfunction [In cooling mode]
Decision Low pressure becomes 14.5psi or below.
[In heating mode]
Conditions
The degree of superheat of suction gas becomes 36 degrees and over.
SH= Ts1 –Te
Ts1: Suction pipe temperature detected by thermistor
Te : Saturated temperature corresponding to low pressure
Supposed
Causes
412
Malfunction is not determined. The unit continues operation.
Gas shortage or refrigerant clogging (piping error)
Defective thermistor (R4T, R7T, R12T, R15T)
Defective low pressure sensor
Defective outdoor unit PC board (A1P)
SiUS34-801A_b
Troubleshooting