99
When isolating the system from the power supply, all
poles of the electrical installation must be disconnec-
ted from the live parts.
■
Check that it is no longer live. Reliably secure the
system against accidental restarting.
■
Ensure that both the mains connection of the indoor
unit and the mains connection of the outdoor unit are
isolated from the power supply. Even if the mains
supply to the indoor unit is switched off, there is still
power to the outdoor unit and vice versa.
Restarting the indoor unit/outdoor unit/system
It is necessary to wait at least 2 min before the indoor
unit, outdoor unit or system are switched on again.
This ensures that residual charges in the system drop
out and fault messages are reliably cleared.
The following start sequence must always be
observed:
1. Switch on power supply to indoor unit.
2. Wait until the default display is shown on the
HMI programming unit.
3. Switch on power supply to outdoor unit.
If this start sequence is not observed, communication
errors are displayed and the system does not start.
Notes on measures involving "Resetting the refrigerant circuit"
!
Please note
Escaping refrigerant will cause environmental
pollution.
Do not unlock refrigerant circuit multiple times in
quick succession.
Unlock refrigerant circuit via ViGuide.
Fault messages
F.1 Lead break, flow temperature sensor
F.1
System characteristics
The heat pump is switched off.
Cause
Lead break, flow temperature sensor, secondary circuit
or heating/cooling circuit 1
Measures
1. Check connection X4.1/X4.2 on the EHCU electron-
ics module:
■
Check wires and plugs for correct seating.
■
Check connections for contact corrosion.
■
Check cables for mechanical damage, e.g. crush-
ing, kinking, chafing or breakage.
2. Check resistor R for NTC 10 kΩ on the disconnected
plug. If R > 300 kΩ, replace the sensor.
3. Replace EHCU electronics module.
F.2 Short circuit, flow temperature sensor
F.2
System characteristics
The heat pump is switched off.
Cause
Short circuit, flow temperature sensor, secondary cir-
cuit or heating/cooling circuit 1
Measures
1. Check the sensor and connection X4.1/X4.2 on
the EHCU electronics module:
■
Check wires and plugs for correct seating.
■
Check connections for contact corrosion.
■
Check cables for mechanical damage, e.g. crush-
ing, kinking, chafing or breakage.
2. Check resistor R for NTC 10 kΩ on the disconnected
plug. If R < 500 Ω, replace the sensor.
3. Replace EHCU electronics module.
Messages
Notes on messages (cont.)
6218234
Diagnosis
To Next Page
Loading...
