51
. Troubleshooting
<Troubleshooting by inferior phenomena>
No.
Fault symptom
Possible cause
Explanation - Solution
1
Main controller display
is blank.
1.
There is no power supply to main
controller.
1. Check LED2 on FTC4 (Master). (See <Figure 4.5.1>.)
(i) When LED2 is lit.
Check for damage or contact failure of the main controller wiring.
(ii) When LED2 is blinking.
Refer to No. 5 below.
(iii) When LED2 is not lit.
Refer to No. 4 below.
2.
Power is supplied to main controller,
however, the display on the main
controller does not appear.
2.
Check the following:
• Disconnection between the main controller cable and the FTC4 (Master)
control board
• Failure of the main controller if “Please Wait” is not displayed.
• Refer to No. 2 below if “Please Wait” is displayed.
2
“Please Wait” remains
displayed on the main
controller.
1.
"Please Wait" is displayed for up to 6
minutes.
1.
Normal operation.
2.
Communication failure between the main
controller and FTC4 (Master).
2, 3. Main controller start up checks/procedure.
(i) If “0%” or “50-99%” is displayed below "Please Wait" there is a
communication error between the main controller and the FTC4 (Master)
control board.
• Check wiring connections on the main controller.
• Replace the main controller or the FTC4 (Master) control board.
(ii) If “1-49%” is displayed there is a communication error between the outdoor
unit's and FTC4 (Master) control boards.
• Check the wiring connections on the outdoor unit control board and the FTC4
(Master) control board.
(Ensure S1 and S2 are not cross-wired and S3 is securely wired with no
damage. (See section 4.1.)
• Replace the outdoor unit's and/or the FTC4 (Master) control boards.
3.
Communication failure between FTC4
(Master) and outdoor unit.
3
The main screen
appears with a press
of the “ON” button, but
disappears in a second.
The main controller operations do not work
for a whilst after the settings are changed in
the service menu. This is because the system
takes time to apply the changes.
Normal operation.
The indoor unit is applying updated settings made in the service menu. Normal
operation will start shortly.
4
LED2 on FTC4 (Master)
is off.
(See <Figure 4.5.1>.)
When LED1 on FTC4 (Master) is also off. (See
<Figure 4.5.1>.)
<FTC4 (Master) powered via outdoor unit.>
1.
The outdoor unit is not supplied at the
rated voltage.
1. Check the voltage across the terminals L and N or L3 and N on the outdoor
power board. (See section 4.1.)
• When the voltage is not 220 to 240V AC, check wiring of the outdoor unit and
of the breaker.
• When the voltage is at 220 to 240V AC, go to “2.” below.
2.
Defective outdoor controller circuit board.
2. Check the voltage across the outdoor unit terminals S1 and S2. (See section
4.1.)
• When the voltage is not 220 to 240V AC, check the fuse on the outdoor
control board and check for faulty wiring.
• When the voltage is 220 to 240V AC, go to “3.” below.
3.
FTC4 (Master) is not supplied with 220 to
240V AC.
3. Check the voltage across the indoor unit terminals S1 and S2. (See section 4.1.)
• When the voltage is not 220 to 240V AC, check FTC4 (Master)-outdoor unit
wiring for faults.
• When the voltage is 220 to 240V AC, go to “4.” below.
4.
FTC4 (Master) failure.
4. Check the FTC4 (Master) control board.
• Check the fuse on FTC4 (Master) control board.
• Check for faulty wiring.
• If no problem found with the wiring, the FTC4 (Master) control board is faulty.
5.
Faulty connector wiring.
5.
Check the connector wiring.
• When the connectors are wired incorrectly, re-wire the connectors referring to
below. (See section 4.1.)
S1
S2
S3
L
N
CN01
CN01
FTC4 (Master)
powered via
outdoor unit
Black
Hydrobox
control board
BLACK
YELLOW
YELLOW
BLACK
