Hitachi YUTAKI Series - Troubleshooting of Control System; System Controller

225
Troubleshooting of control system
SMGB0066 rev.0 - 12/2009
Troubleshooting
Service Manual
7

 
 
Fault codes are displayed in the default display as “FAUL 1” to “FAUL 13”. The table below describes the meaning of the
faultcode,thebehaviourofthesystemduringthatfaultconditionandsuggestedremedialactiontosolvetheproblem.
   
FAUL 0 No fault detected System operates normally
FAUL 1
No supply water temperature
sensor (TSUP) or sensor failure.
Heat Pump and Boiler (or Electric Heater) will be
disabled.
Check sensor operation and sensor wiring.
FAUL 2
No return water temperature
sensor (TRET) or sensor failure.
Thesystemwillcontinuetooperate,buttheheat
pump may operate even when the return temperature
is too high.
Check sensor operation and sensor wiring.
FAUL 3
No mixed water temperature
sensor (TMIX) or sensor failure.
The mixing valve will close and no heating will be
available.
Check sensor operation and sensor wiring.
FAUL 4
No DHW temperature sensor
(TDHW) or sensor failure.
There will be no DHW tank heating available. Check sensor operation and sensor wiring.
FAUL 5
No outdoor temperature sensor
(TEXT) or sensor failure.
Thesystemwillcontinuetooperate,butwithaxed
outdoor temperature of 10°C.
Check sensor operation and sensor wiring.
FAUL 6
Loss of communications with RF
receiver.
Systemwillcontinuetooperate,butnoroominuence
ispossible,andcontrolwillnotfollowthethermostat
time programme.
Check wiring to RF Receiver. Please refer
to the RF Receiver installation guide.
FAUL 7
Loss of connection to the heat
pump control signal.
The heat pump and electric heater will be disabled. Check control wiring to heat pump.
FAUL 8
Water temperature goes above
maximum (mixing system only).
The mixing valve will close to prevent overheating of
underoorsystem.
Ifproblempersists,checksystemsensors
and valve operation.
FAUL 9 Faultnotiedbytheheatpump. Heat Pump and Electric Heater will be disabled.
Refer to the heat pump installation
guide. To allow the electric heater or
boiler to continue operating (manual
release),pressthe+andSELbuttons
simultaneously.
FAUL 10
Failure of the binding between RF
receiver and thermostat
Systemwillcontinuetooperate,butnoroominuence
ispossible,andcontrolwillnotfollowthethermostat
time programme.
Check wiring to RF Receiver. Please refer
to the RF Receiver installation guide.
FAUL 11
Incorrect device connected to RF
receiver terminals.
Systemwillcontinuetooperate,butnoroominuence
ispossible,andcontrolwillnotfollowthethermostat
time programme.
Check wiring to RF Receiver. Please refer
to the RF Receiver installation guide.
FAUL 12
Failure of the RF receiver to
receive messages from the
thermostat.
Systemwillcontinuetooperate,butnoroominuence
ispossible,andcontrolwillnotfollowthethermostat
time programme.
Check wiring to RF Receiver. Please refer
to the RF Receiver installation guide.
FAUL 13
The chosen extension is not
allowedinthisconguration.
The system will continue to operate normally without
the extension.
Selectacongurationwheretheextension
is allowed.
 
Shoulditbenecessarytoresetthecontrollertothefactorydefaultcondition,pressthe
and buttons together during the
power-oncycle.Remembertore-selectthedesiredhydrauliccongurationandsetthenecessaryinstallationparameters.
 
Toadjustonlythetimeduringnormaloperationusethe
or buttonstoadjustthetimeandpressthegreen
buttonagaintoconrmanychanges.