Teddington SECO STEEL 50 Manuel Technique page 31

6 Information on maintenance by specialist operators only.
6.1 Checks to the area
6.1.1 Work procedure
6.1.2 General work area
6.1.3 Checking for presence of refrigerant
6.1.4 Presence of fire extinguisher
6.1.5 No ignition sources
6.1.6 Ventilated area
6.1.7 Checks to the refrigeration equipment
Prior to beginning work on systems containing flammable refrigerants, safety checks are necessary
to ensure that the risk of ignition is minimized. For repair to the refrigerating system, the following
precautions shall be complied with prior to conducting work on the system.
Work shall be undertaken under a controlled procedure so as to minimize the risk of a flammable
gas or vapour being present while the work is being performed.
All maintenance staff 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 off. Ensure that the conditions within the area have been made safe by control of
flammable material.
The area must be checked with a special explosimeter before and during work, so that the
technician can reliably verify the possible presence of potentially flammable atmospheres. It must
be ensured that the leak detection apparatus is suitable for use with flammable refrigerant fluids,
namely:
1) Suitable for detecting the type of gas used in the unit.
(R1234yf: Tetrafluoropropene).
2) Suitable for use in Atex hazardous areas (at least zone 2).
It is forbidden to perform hot working on parts of the unit before this has not been completely
emptied of the flammable refrigerant fluid, and that it has been subjected to an accurate process of
reclamation by inert gas (flushing) in all parts of the circuit. In this regard, see the specific section
relating to the flushing operation. Only at the end of this operation can it be considered that the
refrigerant circuit and its parts no longer contain significant quantities of flammable fluid. In any
case, it is always necessary to have an appropriate flame extinguishing apparatus available.
Personnel who perform maintenance on the unit which requires direct intervention and / or exposure
of pipes that contain or have contained a flammable refrigerant fluid must not use tools or devices
that represent a source of ignition.
All possible ignition sources must be kept away from the place of maintenance, repair, removal and
disposal, operations during which the flammable refrigerant fluid could be accidentally released into
the surrounding space
During maintenance activities, continuous ventilation must be present, so that an accidental dispersion
of flammable refrigerant fluid can be diluted in the atmosphere. Please note that in any case the
dispersion in free air must be considered an extraordinary situation linked to events of an involuntary
or accidental nature
The replacement of the electrical parts of the unit must only be carried out by qualified personnel (see
EN 600079-14). The replacement must be carried out with original and homologous spare parts. Do
not proceed with any replacement if the appropriate spare part is not available. If in doubt, contact the
service centre.
The following checks must be carried out on appliances that use flammable refrigerant fluids:
a. that the ventilation devices and outlets function properly and are not obstructed;
b. if an indirect refrigeration circuit is used, the presence of refrigerant fluid in the secondary circuit
must be checked;
c. the marking on the appliance must remain visible and legible. Markings and graphic signs that
are illegible must be correct;
M.SECOSTEEL 50-00 Manual TEDDINGTON_ITA_UK_DE_FR_ES_DK - 15/07/2021
EN
31