Maintenance Procedures - Panasonic 140 Installation And Maintenance Manual

17.3. Maintenance procedures

17.3.1. Refrigerant circuit
At least once per year, this equipment must be submitted to leakage checks, by a professional authorized to perform such an
operation. Refer to national requirements for the frequency of these checks.
CAUTION Never use the compressor as a vacuum pump to drain the installation.
17.3.1.1. Refrigerating fl uid charge
Run the unit in cooling mode to determine whether the group's charge is correct by checking actual sub-cooling.
17.3.1.2. Compressor oil
Oil for refrigeration equipment is light and transparent. It maintains its colour for a long operating period.
As a refrigeration system designed and installed properly will run without problem, the compressor oil does not require
replacement, even after a long operating period.
Blackened oil has been exposed to impurities in the refrigeration pipework, or excess temperatures on the compressor
backfl ow side, which inevitably degrades oil quality. Blackening oil or degradation of its qualities may also be caused by
humidity in the system. Change the oil when its colour changes or when it is degraded.
In this case, before restarting the unit, the refrigeration circuit must be emptied, purged and recharged accordingly.
Compressors use polyester oil. During maintenance interventions on the compressor, or if the refrigeration
circuit has to be opened at any point, do not forget that this type of oil is highly hygroscopic, and avoid
CAUTION
exposing it to the atmosphere for long periods. If exposed for any length of time, any remaining oil should
be removed and the oil charge replaced.
WARNING Protect the ECOi-W frame so as to get back oil that could fl ow out accidentally.
17.3.1.3. Filter drier
Refrigeration circuits are fi tted with fi lters drier.
The fl uid indicator is used to check the refrigeration fl ow and humidity rate of the refrigerating fl uid. The presence of bubbles
indicates that the fi lter drier is clogged or the charge insuffi cient.
In this event, even after cleaning the cartridge, the air bubbles remain, which means that the system has lost part of its
refrigerating fl uid in one or several points, which must be detected and repaired.
The glass window contains a colour indicator. Comparing the indicator colour with the scale present on the glass window
allows to calculate the humidity rate of the refrigerating fl uid. If excessive, change the fi lter cartridge, run the system for one
day, then check the humidity rate again.
A humidity rate within the preset limits requires no further intervention. If the humidity rate remains too high, change the fi lter
drier again, start the unit, and run it for another day. It may be necessary to repeat this process several time. If excessive
moisture is present, it may be necessary to remove the entire refrigerant charge, then purge and refi ll the system with a virgin
refrigerant charge.
44