Midea MPPD40C User Manual page 8

6.Information on servicing
1)Checks to the area
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.
2)Work procedure
Work shall be undertaken under a controlled procedure so as to minimise the risk
of a flammable gas or vapour being present while the work is being performed.
3)General work area
All maintenance sta and others working in the local area shall be instructed on the
nature of work being carried out. Work in confined spaces shall be avoided. The area
around the workspace shall be sectioned o . Ensure that the conditions within the
area have been made safe by control of flammable material.
4)Checking for presence of refrigerant
The area shall be checked with an appropriate refrigerant detector prior to and
during work, to ensure the technician is aware of potentially flammable atmospheres.
Ensure that the leak detection equipment being used is suitable for use with
flammable refrigerants, i.e. non-sparking, adequately sealed or intrinsically safe.
5)Presence of fire extinguisher
If any hot work is to be conducted on the refrigeration equipment or any associated
parts, appropriate fire extinguishing equipment shall be available to hand. Have a
dry powder or CO2 fire extinguisher adjacent to the charging area.
6)No ignition sources
No person carrying out work in relation to a refrigeration system which involves
exposing any pipe work that contains or has contained flammable refrigerant shall
use any sources of ignition in such a manner that it may lead to the risk of fire or
explosion. All possible ignition sources, including cigarette smoking, should be kept
su ciently far away from the site of installation, repairing, removing and disposal,
during which flammable refrigerant can possibly be released to the surrounding
space. Prior to work taking place, the area around the equipment is to be surveyed
to make sure that there are no flammable hazards or ignition risks. No Smoking signs
shall be displayed.
7)Ventilated area
Ensure that the area is in the open or that it is adequately ventilated before breaking
into the system or conducting any hot work. A degree of ventilation shall continue
during the period that the work is carried out. The ventilation should safely disperse
any released refrigerant and preferably expel it externally into the atmosphere.
8)Checks to the refrigeration equipment
Where electrical components are being changed, they shall be fit for the purpose
and to the correct specification. At all times the manufacturer's maintenance and
service guidelines shall be followed. If in doubt consult the manufacturer's technical
department for assistance. The following checks shall be applied to installations
using flammable refrigerants: The charge size is in accordance with the room size
within which the refrigerant containing parts are installed;
The ventilation machinery and outlets are operating adequately and are not
obstructed; If an indirect refrigerating circuit is being used, the secondary circuit
shall be checked for the presence of refrigerant; Marking to the equipment continues
to be visible and legible. Markings and signs that are illegible shall be corrected;
Refrigeration pipe or components are installed in a position where they are unlikely
to be exposed to any substance which may corrode refrigerant containing
components, unless the components are constructed of materials which are
inherently resistant to being corroded or are suitably protected against being so
corroded.
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