Jc" Indoor Unit: Malfunction Of Low Pressure Sensor - Daikin ALTHERMA HT Service Manual

ESIE09-08B
3.36 "JC " Indoor Unit: Malfunction of Low Pressure Sensor
JC
Remote Control
Display
Subcode 16
All indoor units
Applicable
Models
Malfunction is detected from pressure detected by low pressure sensor.
Method of
Malfunction
Detection
When the low pressure sensor is short circuit or open circuit.
Malfunction
Decision
Conditions
 Defect of low pressure sensor
Supposed
 Connection of high pressure sensor with wrong connection
Causes
 Defect of indoor unit PC board (A4P)
Troubleshooting
1: Voltage measurement point
2: Refer to "Pressure Sensor", pressure/voltage characteristics table on P242.
Troubleshooting
Be sure to turn off power switch before connect or disconnect
connector, or parts damage may be occured.
Caution
The low
pressure sensor is
connected to X18A (blue) of
indoor unit PC board
(A4P).
YES
The
relationship
between the *1VL
and low pressure is
normal (see *2) when voltage is
measured between X18A pins
(2) and (3) indoor unit
PC board (A4P)
(see *1).
NO
Indoor unit PC boa r d A4P
GND
Microcomputer
A/D input
*2 Measu re voltage here.
Troubleshooting by Indication on the Remote Controller
NO
Bad wire connection
value < 0.1 bar
instantly
YES
Faulty sensor
value < 18 bar
over 12 minutes
+5V
Connect low pressure sensor
property and restart system.
Replace indoor unit PC board
(A4P).
Replace the low pressure sensor.
X18A
Red
4
3 Black
White
2
1
(V2809)
177