FläktGroup Multi-DENCO, Operation Manual

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Fault Finding and Troubleshooting Multi -DENCO
104 FläktGroup DC-2013-0101-GB • Subject to modifications • R4-05/2018
These simple questions and observations give important information to an engineer to
be able to appreciate a situation before attending site. The more information you can
provide, the more likely the issue will be solved in a fast and timely manner.
11.1 Common Issues
Below is a list of conventional alarms or issues that, if initially installed and commissio-
ned properly, have a small chance of occurring. Before addressing the fault and pos-
sible remedy, please observe the following:
•
Always refer to the correct electrical drawing for the equipment.
•
Regular maintenance is the most effective measure to preventing any issues.
•
Refrigerant leak testing must only be conducted by suitably qualified engineers
•
If troubleshooting requires adjustments to the controller's settings, please refer to
the separate controller manual before proceeding.
•
All person(s) must know the location of protection features for the unit (e.g. isolation
points) before conducting any work
•
For water based circuits; plant hydraulic settings should not be altered as this may
affect the balance of the complete system. Rebalancing of a system can be a costly
operation, therefore any adjustments must be conducted by qualified individuals
with full knowledge of the system design and requirements.
The following table contains a sample list of mechanical issues and possible remedies
to fix them. A list of common control issues can be found in the separate controller
manual.
NOTE!
The advice in the following section assumes the unit has been operating consi-
stently for a significant amount of time with appropriate design conditions, applica-
tion and all necessary resources are supplied to the unit (electrical power, water,
free airflow etc.).
Multi -DENCO units use fans which are regulated independently by the main control
board. Removing guards whilst unit is operational risks death or serious injury.
Inverters also store energy for a period of time after isolation.
•
Disable the unit.
•
Electrically isolate the unit.
•
Wait AT LEAST 5 minutes
9
Once fan momentum has ceased and the inverter energy discharged, you can
open the doors and conduct work.
NOTE!
Due to the relationship between temperature and humidity, high temperature and
low humidity or alternatively low temperature and high humidity can occur at the
same time. To resolve such situations, always address the temperature first, before
taking measures to resolve humidity.
Fault Possible Reason Possible Remedy
Low pressure in refrigeration sy-
stem (low pressure alarm) Possible leak in pipework Investigate location of leak and repair. Once repair perform
pressure tests and re-commission
Tab. 11-1