Alfa Laval Micro - Page 58

Alfa Laval Micro
Installation, service and operating instruction
56
Symptom
Reason
Action
No heating
Circulation pump not running
Check that the electrical power is on
Check the circulation pump
If the pump fails to start after stopping, try to start
it at the highest setting.
Check the heating parameters in room
thermostat
Summer reduction (Economy function) parameter
2, category 2: If measured outdoor temperature is
higher than target temperature, the pump should
not be operating.
Pump difference (Economy function) parameter 3,
category 2:
If the calculated water supply temperature is not
greater than the outside temperature by this
amount the heating will switch off.
If parameter 3 is set to 0, the pump operation will
not be affected by this parameter.
Heating supply temperature sensor
and outdoor temperature sensor
(option) does not work
Check the heating supply temperature sensor
and outdoor temperature sensor (option)
Check that they are correctly cited and working.
To confirm that sensors are connected and
operating, press the info button on the room
thermostat, check that the specified temperatures
are reasonable.
Loss of function in the heating
control unit.
See 19.5.5 Run the pump manually
Disturbing noise
from the circulation
pump/ Noise in the
radiator system
Pump capacity set too high
Reduce the pump capacity
The pump has been set at a too high capacity
level. Reduce the level by choosing a lower output
setting on the pump.
The lowest setting is the most economical.
Air in the pump
Vent the pump
The pump is self-venting.
Air in the pump may cause noise. This noise
ceases after a few minutes run time.
Quick venting of the pump can be obtained by
setting the pump to speed III for a short period,
depending on system size and design. When the
pump has been vented, i.e. when the noise has
ceased, set the pump according to the
recommendations.
Pump motor or pump component
damaged
See 19.5.6 Change pump components or the
complete pump
Differential pressure control valve
set too high
See 15 Differential pressure control valve, DPC
Heating
temperature
unstable
Heating supply temperature sensor
and outdoor temperature sensor
(option) does not work
Check the heating supply temperature sensor
and outdoor temperature sensor (option)
Check that they are correctly cited and working.
To confirm that sensors are connected and
operating, press the info button on the room
thermostat, check that the specified temperatures
are reasonable