7
X
X
X
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UNIT MAINTENANCE
7.4.3 Compressors
Operations to be performed
Frequency
Every
month
Every
6 months
Every
year
When
required
Inspect the compressors visually
Check the noise and vibrations of the compressors
Check the supply voltage of the compressors
Check the electrical connections of the compressors
Check the oil level in the compressors by means of the dedicated light (if present)
Check that the casing heaters are powered and working properly (if present)
Check the condition of the electrical cables of the compressors and their fixing in the terminals
Monthly operations can be performed directly by the system owner. The other interventions must be carried out by qualified
and adequately trained personnel.
Any cleaning operation is prohibited, before the appliance has been disconnected from the power supply, by turning the
main switch to the OFF position. It is forbidden to touch the appliance barefoot or with wet or damp parts of the body.
Work on the cooling circuit must be carried out by suitably qualified and trained technicians, enabling in compliance with
the current local laws and regulations.
Before the first start-up it is necessary to perform all the operations described in the previous tables and to make the
necessary checks required by the pre-start control form (valid for Italy) to be requested from the service.
7.5
Cooling circuit repair
The system must be filled with nitrogen using a cylinder fitted with a reduction valve up to a pressure of approximately 15 bar.
Any leaks must be identified by a leak detector device. The appearance of bubbles or foam indicates the presence of localised leaks. In this case,
discharge the circuit before carrying out repairs with appropriate alloys..
If leak detection tools are installed on the system, they should be inspected at least once a year to ensure they are working
correctly.
Never use oxygen instead of nitrogen: high risk of explosion.
Cooling circuits operating with refrigerant gas require special care in assembly and maintenance, in order to protect them from malfunctions.
The following are therefore necessary:
• Avoid refilling using oil different from that specified already pre-loaded in the compressor.
• For machines that use refrigerant, if there are gas leaks that result in the circuit being even partially discharged, avoid topping up the
refrigerant, but instead completely discharge the machine, recovering the refrigerant for subsequent disposal and after emptying, refill them
with the specified quantity.
• When replacing any part of the refrigeration circuit, do not leave the circuit open for more than 15 minutes.
• In particular, if the compressor is replaced, complete the installation within the time indicated above, after removing the rubber caps.
• If the compressor is replaced, it is advisable to wash the cooling circuit with suitable products and to insert an antacid filter for a certain
period.
• In empty conditions do not supply voltage to the compressor; do not compress air inside the compressor.
Rev. C 09-2020
MTEC.3810.GB-C-1 Operation and maintenance manual serie WZA English
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