1.16 Comfort
issues
Feature
Possible cause
Corrective action
The compressor does not start.
Fault in power supply.
Check the fuses.
The heat pump is switched off. The
Main Menu window displays .
Switch on the heat pump.
Locking due to repeated alarms.
illuminates continuously in red.
The Main Menu window displays .
Cancel the lockout caused by the alarms.
The time programming of the heat
pump is activated. The Main Menu
window displays .
Set or deactivate the time programming of the heat pump.
STAND-BY
appears on the display.
No service is needed. Check if there is a need.
Waiting for the compressor to start is
active. The Main Menu window
displays .
.
Wait until the specified time xx has elapsed.
The EVU signal is active. The Main
Menu window displays .
Wait until the EVU signal is deactivated.
Low temperature of hot
water.
The hot water programming is active.
Configure or turn off hot water time programming.
Night time programming is active.
The Main Menu window displays .
Set or deactivate night-time programming.
The hot water mode is deactivated.
Activate hot water mode.
The hot water mode is switched off
using the remote control.
Deactivate the hot water remote control.
The temperature of hot water lies
between the default temperature
and the temperature difference.
Increase the default temperature and or decrease the gap
between the starting temperatures.
Temporarily high peak demand.
Wait 15-30 minutes and check the temperature of the hot
water again.
Room temperature:
HEATING in low operating mode,
COOLING in high operating mode.
Incorrect work program.
Select the appropriate program.
Operating mode HEATING/COOLING
is deactivated.
Activate the operating mode HEATING/COOLING.
The outdoor temperature is higher/lower
than the heating/active cooling/passive
cooling off values.
Set the shut-off temperature for heating/active cooling/
passive cooling.
Time programming is activated for
operating mode HEATING/COOLING.
Set or deactivate the HEATING/COOLING time
programming.
Night mode programming is activated.
The Main Menu window displays
.
Set or deactivate night-time programming.
The compressor operates and reaches
the specified supply temperature.
Set the heating/cooling curve and inform the technical
service.
Room terminals do not present a
demand for the heat pump.
Set the default temperature for the room terminals.
Temporarily strict requirements for
air conditioners.
Wait a few hours and check the room temperature again.
Zehnder ComfoBox Q / ComfoHeat User Manual, BA-CBQ_DE-CH V1.0
19
