Daikin EWAD620-C17C-SS, Service Manual, Page: 294 / 304

Maintenance ESIE10-01
5–4 Part 5 – Maintenance
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1.2 System Maintenance
Warning:
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All routine and non-routine maintenance activities on the machine must be carried out solely by
qualified personnel who have been suitably trained and are familiar with the device, its operation
and maintenance, and who are aware of the safety requirements and risks involved.
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It is absolutely forbidden to remove all the protections of the moving parts of the unit.
Attention:
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The causes of repeated shut-downs deriving from triggering of safety devices must be investigated
and corrected. Simply re-starting the alarms may seriously damage the equipment.
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A correct refrigerant and oil change is essential for optimal operation of the machine and for
environmental protection. Any oil and refrigerant recovery must conform to legislation in force.
General
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Important:
Besides the checks suggested hereto, in order to keep the unit at optimal performance levels and
efficiency and prevent malfunction, it is recommended to schedule periodical inspections of the
unit by qualified personnel. Specifically, the following is recommended:
• 4 inspections per year (every three months) for units running about 365 days per year.
• 2 inspections per year (1 at seasonal start-up and the second mid-season) for units running
about 180 days per year.
• 1 inspection per year (at seasonal start-up) for units running about 90 days per year.
Regular checks and routine controls should be considered extremely important both during initial
start-up and regularly during operation. These checks also include suction and condensation
pressures, the sight glass on the liquid line and that the superheating and subcooling parameters, read
through the microprocessor installed on the machine, fall within the range of operating parameters.
A recommended ordinary maintenance programme is given at the end of this chapter, whilst an
operating data collection card is at the end of the manual. We recommend recording all machine
operating parameters on a weekly basis. The collection of this data will also be very useful for
technicians, should technical assistance be required.
Compressor
maintenance
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Important:
Although the single-screw compressor is of a semi-hermetic type and therefore does not need
scheduled maintenance, for the purposes of keeping the compressor at optimal levels of perform-
ance and efficiency and to prevent malfunction, we recommend a visual check on the sate of sat-
ellite wear every 10000 hours of operation, and a measurement of satellite-screw coupling
tolerance. This inspection must be carried out by qualified, trained personnel.
Vibration analysis is a good method for verifying the mechanical conditions of the compressor.
Verification of vibration readings immediately after start-up and periodically on an annual basis is
recommended. The compressor load must be similar to the previous measurement's load to ensure
measurement reliability.
Lubrication The units do not require a routine procedure for lubrication of components. The fan bearings are
permanently lubricated and as such no additional lubrication is required.
Compressor oil is synthetic and highly hygroscopic. It is therefore advised to limit its exposure to the
atmosphere during storage and filling. It is recommended that oil is exposed to the atmosphere for a
period of no more than 15 minutes. The compressor oil filter is positioned above the oil separator
(delivery side). Replacement is recommended when its pressure drop exceeds 2.0 bar. The pressure
drop across the oil filter is the difference between the compressor discharge pressure and oil pressure.
Both these pressures can be monitored through the microprocessor for both compressors.