Panasonic CS-YU18ZKA, Operating Instructions Manual

28

 Safety Precautions

8. Removal and evacuation

• When breaking into the refrigerant circuit 

to make repairs – or for any other purpose 
– conventional procedures shall be used. 
However, it is important that best practice is 
followed since 

fl

 ammability is a consideration. 

The following procedure shall be adhered to: 
remove refrigerant -> purge the circuit with 
inert gas -> evacuate -> purge with inert gas 
-> open the circuit by cutting or brazing.

• The refrigerant charge shall be recovered into 

the correct recovery cylinders.

• The system shall be purged with OFN to 

render the appliance safe.

• This process may need to be repeated 

several times.

• Compressed air or oxygen shall not be used 

for this task.

• Purging shall be achieved by breaking 

the vacuum in the system with OFN and 
continuing to 

fi

ll until the working pressure is 

achieved, then venting to atmosphere, and 

fi

nally pulling down to a vacuum.

• This process shall be repeated until no 

refrigerant is within the system.

• When the 

fi

 nal OFN charge is used, the 

system shall be vented down to atmospheric 
pressure to enable work to take place.

• This operation is absolutely vital if brazing 

operations on the pipe work are to take place.

• Ensure that the outlet for the vacuum pump is 

not close to any potential ignition sources and 
there is ventilation available.

OFN = oxygen free nitrogen, type of inert gas.

9. 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 in an appropriate 

position according to the instructions.

- Ensure that the refrigerating 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 over 

fi

ll 

the refrigerating system.

• Prior to recharging the system it shall be 

pressure tested with OFN (refer to #7).

• 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.

• Electrostatic charge may accumulate and 

create a hazardous condition when charging 
and discharging the refrigerant. To avoid 

fi

 re 

or explosion, dissipate static electricity during 
transfer by grounding and bonding containers 
and equipment before charging/discharging.

10. Decommissioning

• Before carrying out this procedure, it is 

essential that the technician is completely 
familiar with the equipment and all its details.

• 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 
recovered 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 protective 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.