Troubleshooting
When cooling or dehumidifying, the compressor (
-6M1
) is operating continuously. So is the condenser.
Please check the condenser at its fan wheel, which must continuously operate to carry off the heat.
In standard case the injection
points (a → cooling) and (b → dehumidification) (Figure 59) of the capillary
tubes are cold. Otherwise, the flow of the refrigerant is disturbed.
Possible causes:
•
Solenoid valve (-
7Y1
) for cooling closed
Check the function of the valves by switching off the humidity switch (
-8S1
) (chap. 4.4).
•
Solenoid valve (-
7Y2
) for dehumidification closed
Check the valve by switching on the humidity switch (
-8S1
), heating the unit and dehumidifying
at the same time. During regulation, the valve must be open.
If no deviation of the measured values was noted at the described tests, check the cooling cycle.
If the injection points a, b) of the capillary tubes are not cold, possible reasons are:
•
the capillary tubes are blocked (chap. 10.4)
•
loss of refrigerant in the cooling cycle
The repair of the cooling system must only be carried out by service personnel with
specialized training as cooling technician.
To avoid repair attempts by unqualified personnel, repair of the cooling system is not
described in this service manual.
Qualified for service and maintenance work on the cooling system is only staff that has a certification in
accordance with regulation 303/2008/EC and expert knowledge in accordance with EN 13313:2010.
Personnel should be trained for the maintenance of the cooling system and be familiar with the content
of the service manual and operating manual.
R 134a is used as refrigerant in the KBF.
The amount of refrigerant may differ due to technical reasons.
The amount of refrigerant for a unit is specified on its type plate.
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Service Manual KBF (E5.2) 04-2015