Alfa Laval Micro - STC Service Instructions

Alfa Laval Micro
Installation, service and operating instruction
55
Symptom
Reason
Action
Heating system
temperature too
high or too low
Filter for heating media clogged
See 19.5.2 Check if the filter for heating media is
blocked.
Differential pressure control valve
incorrectly adjusted (option
See 15 Differential pressure control valve, DPC.
No heating
Closed radiator or floor heating
valves
Check that all radiator valves and floor heating
valves are fully open
Filter for heating media clogged
See 19.5.2 Check if the filter for heating media is
blocked.
Differential pressure control valve
incorrectly adjusted(option)
See 15 Differential pressure control valve, DPC
Heating
temperature
unstable
Alternating pressure on primary
side
Check available differential pressure and
temperature at the primary heating medium
provider
Filter for heating media clogged
See 19.5.2 Check if the filter for heating media is
blocked.
Differential pressure control valve
incorrectly adjusted (option)
See 15 Differential pressure control valve, DPC
STC service instructions 19.2
Hand manoeuvre of the heating actuator
The room thermostat must be without current when manoeuvring the actuator by hand.
NOTE: if manually adjusting the actuator, the operator control panel must be restarted before use.
Symptom
Reason
Action
Heating system
temperature too
high or too low
The heating control equipment may
need to be adjusted
Check and adjust the heating curve
See 12.2 CM737-Installer parameters table and
change the selected heating curve with parameter
15 category 1.
If needed the set heating curve can be fine-tuned.
Increase/ decrease the room temperature to
parallel adjust the heating curve.
Also see section 9.1 OTC heating curve and 9.2
Parallel adjustment of heating curve.
Heating valve and/or actuator does
not work
See 19.5.4 Check the actuator and valve function
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.