Daikin Altherma HT - Page 167

ESIE09-08B Troubleshooting by Indication on the Remote Controller
Troubleshooting 155
Troubleshooting
:  Refer to information on page 209.
Caution
Be sure to turn off power switch before connect or disconnect
connector, or parts damage may be occured.
NO
YES
NO
YES
NO
YES
CHECK 2
Is the
stop valve
open?
Open the stop valve.
 Mount a pressure gauge on the low-pressure service port.
 Connect the Service Tool.
 Reset the operation using the remote control, and then restart
the operation.
Are the
characteristics of
the low pressure sensor
normal? (See
*1.)
Replace the low pressure sensor.
Is the
pressure
detected with the PC
board normal?
(See *2.)
Replace the control PC board (A4P)..
· The low pressure sensor is normal, and the pressure
detected with the PC board is also normal.
· The low pressure has really become low.
Refer to “remove the causes by which the low
pressure has become low”.
*1: Make a comparison between the voltage of the pressure sensor (*4) and that read by the
pressure gauge.
(As to the voltage of the pressure sensor, make measurement of voltage at the connector,
and then convert it to pressure.)
*2: Make a comparison between the low pressure value checked with the Service Tool
and the voltage of the pressure sensor (see *1).
*3: Make measurement of voltage of the pressure sensor.
+5V
(4)
(3)
(2)
(1)
Connector for low pressure sensor
Micro controller
A/D input
Make measurement of DC voltage between these wires. (*4)
(Blue)
Red
Black
White
Low
pressure
sensor
Check No.2