Prior to beginning work on systems containing flammable refrigerants, safety checks are necessary to ensure
that the risk of ignition is minimised. For repair to the refrigerating system, the following precautions shall be
complied with prior to conducting work on the system.
CAUTION
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges or any other
adverse environmental effects. The check shall also take into account the effects of aging or continual vibration
from sources such as compressors or fans.
7. INFORMATION SERVICING
7.16 CHARGING PROCEDURES
In addition to conventional charging procedures, the following requirements shall be followed:
Ensure that contamination of different refrigerants does not occur when using charging equipment. Hoses or
lines shall be as short as possible to minimize the amount of refrigerant contained in them.
Cylinders shall be kept upright.
Ensure that the refrigeration system is earthed prior to charging the system with refrigerant.
Label the system when charging is complete(if not already).
Extreme care shall be taken not to overfill the refrigeration system.
Prior to recharging the system it shall be pressure tested with OFN. The system shall be leak tested on
completion of charging but prior to commissioning. A follow up leak test shall be carried out prior to leaving the
site.
7.17 DECOMMISSIONING
Before carrying out this procedure, it is essential that the technician is completely familiar with the equipment and
all its detail. It is recommended good practice that all refrigerants are recovered safely. Prior to the task being
carried out, an oil and refrigerant sample shall be taken.
In case analysis is required prior to re-use of reclaimed refrigerant. It is essential that electrical power is available
before the task is commenced.
a) Become familiar with the equipment and its operation.
b) Isolate system electrically
c) Before attempting the procedure ensure that:
mechanical handling equipment is available, if required, for handling refrigerant cylinders;
all personal protetive equipment is available and being used correctly;
the recovery process is supervised at all times by a competent person;
recovery equipment and cylinders conform to the appropriate standards.
d) Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that refrigerant can be removed from various parts of the
system.
f) Make sure that cylinder is situated on the scales before recovery takes place.
g) Start the recovery machine and operate in accordance with manufacturer s instructions.
h) Do not overfill cylinders. (No more than 80% volume liquid charge).
i) Do not exceed the maximum working pressure of the cylinder, even temporarily.
j) When the cylinders have been filled correctly and the process completed, make sure that the cylinders and the
equipment are removed from site promptly and all isolation valves on the equipment are closed off.
k) Recovered refrigerant shall not be charged into another refrigeration system unless it has been cleaned and
checked.
7.18 LABELLING
Equipment shall be labelled stating that it has been de-commissioned and emptied of refrigerant. The label shall
be dated and signed. Ensure that there are labels on the equipment stating the equipment contains flammable
refrigerant.
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7.19 RECOVERY
CAUTION
When removing refrigerant from a system, either for service or decommissioning, it is recommended good
practice that all refrigerants are removed safely.
When tranferring refrigerant into cylinders, ensure that only appropriate refrigerant recovery cylinders are
employed. Ensure that the correct numbers of cylinders for holding the total system charge are available. All
cylinders to be used are designated for the recovered refrigerant and labelled for that refrigerant(i.e special
cylinders for the recovery of refrigerant). Cylinders shall be complete with pressure relief valve and associated
shut-off valves in good working order.
Empty recovery cylinders are evacuated and, if possible, cooled before recovery occurs.
The recovery equipment shall be in good working order with a set of instructions concerning the equipment that
is at hand and shall be suitable for the recovery of flammable refrigerants. In addition, a set of calibrated
weighing scales shall be available and in good working order.
Hoses shall be complete with leak-free disconnect couplings and in good condition. Before using the recovery
machine, check that it is in satisfactory working order, has been properly maintained and that any associated
electrical components are sealed to prevent ignition in the event of a refrigerant release. Consult manufacturer if
in doubt.
The recovered refrigerant shall be returned to the refrigerant supplier in the correct recovery cylinder, and the
relevant Waste Transfer Note arranged. Do not mix refrigerants in recovery units and especially not in cylinders.
If compressors or compressor oils are to be removed, ensure that they have been evacuated to an acceptable
level to make certain that flammable refrigerant does not remain within the lubricant. The evacuation process
shall be carried out prior to retruning the compressor to the suppliers. Only electric heating to the compressor
body shall be employed to accelerate this process. When oil is drained from a system, it shall be carried out
safely.
7. INFORMATION SERVICING
7.20 TRANSPORTATION, MARKING AND STORAGE FOR UNITS
1. Transport of equipment containing flammable refrigerants
Compliance with the transport regulations
2. Marking of equipment using signs
Compliance with local regulations
3. Disposal of equipment using flammable refrigerants
Compliance with national regulations
4. Storage of equipment/appliances
The storage of equipment should be in accordance with the manufacturer’s instructions.
5. Storage of packed (unsold) equipment
Storage package protection should be constructed such that mechanical damage to the equipment inside the
package will not cause a leak of the refrigerant charge.
The maximum number of pieces of equipment permitted to be stored together will be determined by local
regulations.
GB