Ferroli OMNIA ST 3.2 Handbuch Für Installation, Betrieb Und Wartung Seite 123

OMNIA ST 3.2
Symptom 5: The water pressure relief valve leaks
Possible causes
Dirt has blocked the water safety valve.
Symptom 6: Space heating capacity shortage at low outdoor temperatures
Possible causes
The backup system electric heater operation is
not activated.
A high heating capacity is required in DHW mode
or some parameters are not set correctly (only ap-
plicable to installations with DHW tank ).
Symptom 7: Heat mode can't change to DHW mode immediately
Possible causes
The volume of ACS tank is too small and the
position d she water temperature probe not high
enough.
Symptom 8: DHW mode can't change to Heat mode immediately
Possible causes
Insufficient surface of the DHW tank coil
The heating load of the system is reduced
The disinfection function is enabled but without
TBH
Switching manual FAST DHW function, in this
case the heat pump may switch to the heating
mode for the plant only after the setpoint of the
DHW tank has been satisfied
DHW mode priority
Symptom 9: DHW mode heat pump stop work but setpoint not reached, space heating require heat but unit stay in DHW mode
Possible causes
Insufficient surface of the DHW tank coil
TBH or AHS not available
Corrective action
Check the correct operation of the safety valve by turning the red knob on the valve counterclockwise:
If you do not hear a clicking noise, contact your local technical support service.
If water continues to flow out of the unit, close the water inlet and outlet shut-off valves
and then contact your local technical assistance service.
Corrective action
Check that the backup system electric heater is enabled ( see "9.2 Service parameters table" on page 117 ).
Check whether the thermal protection of the backup system electric heater has been activated or not.
Check if the electric heater of the DHW tank is working, the backup heater and the electric heater of the DHW tank cannot
work at the same time.
Check that the parameters " t_DHWHP_MAX " and " t_DHWHP_RESTRICT " are configured in an appropriate manner:
Ensure that the parameter " DHW Priority " is = 0 (priority ACS disabilitat in ) . • Enable the DHW boiler electric resistance
(TBH, see "9.2 Service parameters table" on page 117 ) .
Corrective action
Set the "dT1S5" parameter to the maximum value .
Check that the " Dhw Priority " parameter is = 1 (DHW priority enabled).
If the " Dhw Priority " parameter = 0 , set the " t_DHWHP_RESTRICT " parameter to the minimum value (the suggested
value is 60min).
Set dT1SH to 2°C.
Enable DHW boiler electric resistance (TBH, see "9.2 Service parameters table" on page 117 ).
If TBH and AHS are not available, try changing the position of the T5 probe by moving it higher.
Corrective action
Set the parameter " Dhw Priority " = 0 and set the parameter " t_DHWHP_MAX " to the minimum value ( the suggested
value is 60min ).
Normal, it does not require heating.
Disable the disinfection function.
Add TBH or AHS for the DHW mode and for anti-legionella disinfection.
Manual deactivation of the FAST DHW function.
If the " Dhw Priority " parameter = 1 , the heat pump will be able to switch to system heating mode only after the setpoint
of the DHW tank has been satisfied.
Corrective action
Set the parameter " Dhw Priority " = 0 and set the parameter " t_DHWHP_MAX " to the minimum value (the suggested
value is 60min).
If the " Dhw Priority " parameter = 1, the heat pump will be able to switch to system heating mode only after having satisfied
the DHW setpoint .
If the " Dhw Priority " parameter = 0, the heat pump will remain in DHW mode for the time defined by the " t_DHWHP_MAX"
parameter.
Add TBH or AHS for DHW mode.
Cod. 3541V991 - Rev. 05 - 06/2022
123
EN