Electronics
Immersion heater card (AA1)
IndicationLED
A steady light means that the relevant
relay is engaged.
K1 - K9: Or-
ange
FunctionOutput
Supply L1K1
Supply L2K2
Supply L3K3
Immersion heater EB1 2 kWK4
Not usedK5
Immersion heater EB1 2 kWK6
Immersion heater EB1 only at 3 kWK7
Immersion heater EB1 2 kWK8
Immersion heater EB1 1 kW or 3 kWK9
Base card (AA2)
IndicationLED
A steady light means that 12 V is OK.Power:
Green
Flashing once/sec. Indicates that the
processor is OK.
Run: Green
Flashes irregularly during communication.Com: Green
Continuous light during active output.PWM1: Or-
ange
Continuous light during active output.PWM2: Or-
ange
A steady light means that the relevant
relay is engaged.
K1 - K4: Or-
ange
Outputs
FunctionOutput
Control signal Circulation pump GP1PWM
Reversing valve (QN10).K1
Circulation pump (GP6).K2
Circulation pump (GP1).K3
No function.K4
Inputs
FunctionOutput
Temperature sensor, hot water, top BT7AA2-X3-3
Temperature sensor, hot water, charging
BT6
AA2-X3-5
Temperature sensor, heating medium
supply, BT2
AA2-X3-7
Temperature sensor, heating medium
supply after immersion heater BT63
AA2-X3-13
Temperature sensor heating medium re-
turn BT3
AA2-X3-19
Input circuit board (AA3)
Inputs
FunctionInputs
Current sensor (GND).AA3-X4-1
Current sensor (BE1).AA3-X4-2
Current sensor (BE2).AA3-X4-3
Current sensor (BE3).AA3-X4-4
Outdoor temperature sensor (BT1).AA3-X6-1
Room sensor (BT50).AA3-X6-3
External supply temperature sensor BT25.AA3-X6-5
AUX1AA3-X6-9
AUX2AA3-X6-11
AUX3AA3-X6-13
AUX4AA3-X6-15
AUX5AA3-X6-17
Outputs
FunctionOutput
Potential free relay CommonK1X7:1
Potential free relay NOK1X7:2
Potential free relay NCK1X7:3
NIBE™ VVM 320Chapter 5 | Component description40