
– Wait until the hot water has heated up. Temporarily in-
creased hot water capacity can be activated in the " Hot
water" home screen or in menu 2.1.
• Too low hot water setting.
– Enter menu 2.2 and select a higher demand mode.
• Low hot water access with the “Smart Control”
function active.
– If the hot water usage has been low for an extended
period of time, less hot water than normal will be pro-
duced. Activate " More hot water" in menu 2.1.
• Too low or no operating prioritisation of hot water.
– Contact your installer!
• "Holiday" activated in menu 6.1.
– Enter menu 6.1 and deactivate.
LOW ROOM TEMPERATURE
• Closed thermostats in several rooms.
–Set the thermostats to max in as many rooms as possible.
Adjust the room temperature via home screen heating,
rather than choking the thermostats.
• S1155PC/S1255PC in incorrect operating mode.
– Contact your installer!
• Too low set value on the automatic heating control.
– Go to the Smartguide for help in increasing heating. You
can also change the heating in the " Heating" home screen.
• Too low or no operating prioritisation of heat.
– Contact your installer!
• "Holiday mode" activated in menu 6.1.
– Enter menu 6.1 and deactivate.
• External switch for changing room temperature activ-
ated.
– Check any external switches.
• Air in the climate system.
– Vent the climate system.
• Closed valves to the climate system.
– Open the valves (contact your installer for assistance in
finding them).
HIGH ROOM TEMPERATURE
• Too high set value on the automatic heating control.
– Go to the Smartguide for help in decreasing heating. You
can also change the heating from the home screen heat-
ing.
• External switch for changing room temperature activ-
ated.
– Check any external switches.
UNEVEN ROOM TEMPERATURE.
• Incorrectly set heating curve.
– Fine-tune the heating curve in menu 1.30.1.
• Too high set value on "dT at DOT"..
– Contact your installer!
• Uneven flow over the radiators.
– Contact your installer!
LOW SYSTEM PRESSURE
• Not enough water in the climate system.
– Fill the climate system with water and check for leaks. In
event of repeated filling, contact the installer.
THE COMPRESSOR DOES NOT START
• There is no heating or cooling demand, nor hot water
demand or pool demand.
There is neither heating or cooling demand, nor hot
water demand.
– S1155PC/S1255PC does not call on heating, cooling or
hot water.
• Compressor blocked due to the temperature condi-
tions.
–Wait until the temperature is within the product’s working
range.
• Minimum time between compressor starts has not
been reached.
– Wait for at least 30 minutes and then check if the com-
pressor has started.
• Alarm tripped.
– Follow the display instructions.
WHINING NOISE IN THE RADIATORS
• Closed thermostats in the rooms and incorrectly set
heating curve.
–Set the thermostats to max in as many rooms as possible.
Fine-tune the heating curve via home screen heating,
rather than choking the thermostats.
• Circulation pump speed set too high.
– Contact your installer!
• Uneven flow over the radiators.
– Contact your installer!
15Chapter 6 | Disturbances in comfortNIBE S1155PC/S1255PC