Table of Contents
[ IX Troubleshooting ]
[7] Servicing the HBC controller
3-way valve
1. 3-way valve, Refrigerant flow adjust valve
MV1 and MV2 (3-way valves) and FCV (water flow rate control valve) are driven by the pulse signal from the HBC controller
control board and are controlled by a stepping motor.
1) HBC controller control board and 3-way valves (MV1, MV2)
4
3
Limit signal
2
(Opening
"0" signal)
1
2) HBC controller control board and water flow rate control valve (FCV)
4
3
Limit signal
2
(Opening
"0" signal)
1
3) Pulse signal output and valve motion
Output (phase)
number
4
5
7
8
If the LEDs (MV1a- MV1h, MV2a-MV2h, FCV3a-FCV3h) on the control board are lit, check the relevant three-way valves and
the refrigerant flow control valves for loose connectors and faulty wiring. Make sure that the valves are properly controlling the
refrigerant flow.
If the LED is unlit, check all three-way valves and refrigerant flow adjust valves for proper operation.
If the problem persists after taking the above measures, replace the circuit board.
HWE1113B
5
5
6
M
6
8
6
7
8
7
4
3
2
1
5
5
6
M
6
8
6
7
8
7
4
3
2
1
Output status
1
2
ON
ON
OFF
OFF
ON
ON
OFF
OFF
ON
ON
OFF
OFF
Circuit board
8
7
6
5
4
3
2
1
Circuit board
5
4
3
2
1
3
2
1
3
4
OFF
When valve opens (1600 0): 4 3 2 1
OFF
When valve closes (0 1600): 1 2 3 4
ON
ON
- 237 -
12V
LED
Microcomputer
12V
GND
LED
Microcomputer
GND
12V
12V
GB
- Quick Links:
- Error Code Lists
Hide quick links:
Table of Contents
Troubleshooting
