National Lab OCGE 111, Operating And Maintenance Manual, Page: 24 / 194

24
The modalities for programming and error message encoding vary according to which type of operating thermostat
is being used.
To avoid damage to the components, you should avoid operating the chiller witho ut cooling medium
at all costs, even for a short period of time! Neither may it be operated when the liquid level dis-
played by the level indicator in the tank falls below the minimum limit. Otherwise the operating cy-
cle of the circulation pumps will stop!
If the display shows lower or higher temperatures than the standard values during operation, switch off the chiller
immediately. Check the operating conditions before you contact the supplier or manufacturer.
6.5.2 TEMPORARY DECOMMISSIONING
All work on the chiller must be carried out by specialist personnel!
Follow this procedure if you need to shut down the chiller:
- Stop the chiller and permanently isolate it from the electricity mains.
- Once you have properly isolated the chiller from the mains, you can disconnect the power cable.
- Open the bypass valves (if present) for the cooling medium circuit and isolate the chiller from the circuit by clos-
ing the stop valves for the feed and return lines at the inlet and outlet as necessary.
- Disconnect the machine from the cooling medium lines.
- Empty the tank and the internal cooling medium circuits.
Never open the cooling medium circuit, which is closed to the atmosphere, (compressor, evaporator
and condenser) if there may be any refrigerant or lubricating oil present.
See Section 5.2.1 for reinstalling the chiller.
6.5.3 DECOMMISSIONING FOR TRANSPORT PURPOSES
All work on the chiller may only be conducted by specialist personnel!
Follow this procedure if you need to shut down the chiller:
- Stop the chiller and permanently disconnect it from the electricity mains.
- Once you have properly isolated the chiller from the mains, you can disconnect the power cable.
- Open the bypass valves (if present) for the cooling medium circuit and isolate the chiller from the circuit by clos-
ing the stop valves for the feed and return lines at the inlet and outlet as necessary.
- Disconnect the machine from the cooling medium lines.
- Empty the tank and the internal cooling medium circuits.
- If the chiller has to be dispatched, use the original or a similar packaging and keep the chiller in an upright position.
- Remove the residual cooling medium from the chiller, taking due account of its characteristics and in compliance
with the relevant legislation in force.
Before dismantling any electrical components, make sure that the chiller is isolated from
the electricity mains and affix a warning sign to prevent the chiller being accidentally re-
connected to the mains!
To ensure that the chiller operates properly and is suitably located, adhere to the safety pre-
cautions described in the relevant sections!
Never open the cooling medium circuit, which is closed to the atmosphere, (compressor,
evaporator and condenser) if there may be any refrigerant or lubricating oil present.
7. MAINTENANCE
MAINTENANCE OPERATIONS
All maintenance work may only be carried out by specialist personnel!
Isolate the chiller from the electricity mains before you carry out any work!
Exercise due caution when cleaning with compressed air and use the recommended personal
protective devices to avoid any damage to your eyes!