Ii.11.3 Special Maintenance - RHOSS ELECTA-ECO THAITI 106 Instrucciones De Uso

II.11.3 SPECIAL MAINTENANCE

II.11.3.1 Component replacement instructions
If a unit requires repair, switch it off and recover the refrigerant fluid
from both the high and low-pressure sides and in the liquid line. This is
because, if the refrigerant fluid is only drained from the high pressure
side, the compressor springs may close together, thereby preventing
the pressure from equalising. In this way, the low pressure part of the
casing and the inlet line could remain pressurised. In this case, if you
apply a brazing torch to one of the low-pressure components of the
system, the pressurised mixture of refrigerant fluid and oil could blow
out of the circuit and ignite upon contact with the brazing torch. To
prevent this risk it is important to make sure that the pressure on the
high and low pressure sides have actually been drained before
desoldering.
II.11.3.2 Restoring the amount of refrigerant fluid
DANGER!
Use suitable personal protection and make sure
you have fire prevention equipment readily
available; in particular, a CO
loading place.
The units are factory-tested with the amount of gas necessary for
correct operation. The amount of gas inside each circuit is shown on the
serial no. plate. When restoring the amount or topping it up, take into
account the environmental and operational conditions of the unit.
Should the R32 need to be topped-up, drain and evacuate the circuit,
eliminating traces of non-condensable gases with any humidity.
 Turn off the unit;
 Drain the refrigerant according to the safety measures;
 Create a vacuum in the unit by connecting the loading valve, the
pressure gauge and the vacuum pump using flexible pipes (refer to
the figure below);
 Once the operation is completed, keep the pressure inside the unit
below 80Pa for at least 30 minutes so as to make sure there is no
leak whatsoever.
M
TF
PV
Then top-up the exact amount of refrigerant as shown on the serial no.
plate. The refrigerant must be added from the load cylinder in the liquid
state. It must be restored as follows, after any maintenance and
washing the circuit thoroughly:
 Install an anti-acid filter on the intake to the compressor and have the
unit run for at least 24 hours;
 Check the acidity degree and change the refrigerant fluid and oil if
needed and then let the unit run for at least 24 hours;
 Remove the anti-acid filter cartridge.
Once the topping-up operation is complete, repeat the unit start-up
procedure and monitor its operating conditions for at least 24 hours.
cylinder near the
2
Manometer
Flexible hoses
Vacuum pump
Rapidly filling with refrigerant on the inlet side of a single-phase system
may prevent the compressor from starting or cause a breakage. The
best way to avoid this situation is to fill both high and low pressure sides
simultaneously.
If, for any particular reason, you wish to simply top-up the refrigerant,
bear in mind that there may be a slight drop in unit performance.
II.11.3.3 Removing refrigerant fluid from the unit
When removing refrigerant from a system, for maintenance or
decommissioning purposes, it is advisable to make sure that all
refrigerants are removed safely. Make sure that the correct number of
containers is available for the entire amount of the system. All
containers to be used for this purpose must be suitable for the disposal
of refrigerant and bear a label that specifies their use for that refrigerant.
The containers must be complete with a pressure limiting valve and fully
functional dedicated shut-off valves. Once emptied, the containers must
be cooled prior to disposal. The recovery equipment must be in good
condition, accompanied by the specific instructions and suitable for the
recovery of flammable refrigerants. A set of calibrated scales must also
be available and in good condition.
The pipes must be complete with disconnection joints without leaks.
Before using the refrigerant removal device, check that it works well,
that it has been stored properly and that the relevant electrical
components are sealed so as to prevent the ignition of flames in the
event of refrigerant leaks. If in doubt, consult the manufacturer.
If compressors or their oil need to be removed, make sure they have
been evacuated to an acceptable level so as to prevent flammable
refrigerants from remaining in contact with the lubricant. The evacuation
process must be carried out before returning the compressor to the
suppliers. To accelerate this process, only the compressor casing
heater can be used. The oil must be safely drained from the system.
Before performing this procedure, it is essential for the technician to be
familiar with the equipment. It is good practice for all refrigerants to be
recovered safely. A sample of oil and refrigerant must be taken before
the actual decommissioning if an analysis is required before re-using
the recovered refrigerant. It is essential for electricity to be available
before starting the activity.
Then follow the steps below:
1. be familiar with the equipment and its operation;
2. isolate the system electrically;
3. before performing the procedure, make sure that:
 mechanical handling equipment is available, if necessary, for
handling refrigerant containers;
 all personal protective equipment is available and used correctly;
 the recovery process is supervised at all times by a competent
person;
 recovery equipment and containers comply with the appropriate
standards.
4. drain the refrigerant from the circuit, if possible;
5. if point 4 cannot be completed, install a sleeve so that the refrigerant
can be removed from various parts of the system;
6. make sure the container is on the scale before recovery begins;
7. start up the refrigerant removal device and proceed according to the
manufacturer's instructions;
8. do not overfill the containers (not more than 80% of volumetric liquid
amount);
9. do not exceed the maximum working pressure of the container;
10. when the containers have been filled correctly and the process is
completed, make sure that these and the equipment are immediately
removed from the site and all isolation valves on the equipment are
closed;
11. the recovered refrigerant must not be added to another cooling
system, unless it has been cleaned and checked.
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ELECTA-ECO