Daikin Altherma HT Service Manual

ESIE09-08B Troubleshooting by Indication on the Remote Controller
Troubleshooting 175
3.34 “JA ” Indoor Unit: Malfunction of High Pressure Sensor
Remote Control
Display
JA
Subcode 16
Applicable
Models
All indoor units
Method of
Malfunction
Detection
Malfunction is detected from the pressure detected by the high pressure sensor.
Malfunction
Decision
Conditions
When the high pressure sensor is short circuit or open circuit.
Supposed
Causes
 Defect of high pressure sensor
 Connection of low pressure sensor with wrong connection
 Defect of indoor unit PC board (A4P)
Troubleshooting
1: Voltage measurement point
2: Refer to “Pressure Sensor”, pressure / voltage characteristics table on P242.
Caution
Be sure to turn off power switch before connect or disconnect
connector, or parts damage may be occured.
(V2806)
Replace the high pressure sensor.
NO
NO
Replace indoor unit PC board
(A4P).
YE S
YES
Bad wire connection
Value < 0.1 bar
over 60 seconds
Value > 43 bar
over 60 seconds
Faulty sensor
Connect the high pressure sensor
and turn on again.
The high
pressure sensor is
connected to X17A of
indoor unit PC
board (A4P).
Indoor unit PC board A4P
+5V
X17A
Red
Black
White
GND
*2 Measure DC voltage here.
High pressure sensor
4
3
2
1
(V2807)
Microcomputer
A/D input

Daikin Altherma HT Specifications

General

Type	Air-to-water heat pump
Refrigerant	R-410A
Water Outlet Temperature	Up to 80°C
Operating Temperature Range	-20°C to 35°C
Power Supply	3-phase, 400V
Energy Efficiency Class (Heating)	A++