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WARNING
A critical shift of the refrigerant ignition limit is
possible.
Avoid air penetration!
3.1
Use of flammable refrigerants of the A2L
safety group
Information
The information in this chapter about the use of
refrigerants of the A2L safety group refer to
European regulations and directives. In regions
outside the EU, observe the local regulations.
This chapter describes the additional residual risks
posed by the condensing compressor when using A2L
safety class refrigerants and provides explanations.
This information helps the system manufacturer carry
out the required risk assessment. The information
alone can in no way replace the risk assessment for the
system.
Design, maintenance and operation of refrigeration sys-
tems using flammable refrigerants of the A2L safety
class are subject to particular safety regulations.
When installed in accordance with these operating in-
structions and under normal operating conditions
without malfunction, the compressors are free from ig-
nition sources that could ignite the flammable refriger-
ants of the A2L safety group. They are considered
technically tight. The compressors are not designed for
operation in an Ex zone. The compressors have not
been tested for use with flammable refrigerants in ap-
plications according to the UL standard or in units ac-
cording to EN/IEC60335 standards.
Information
When using a flammable refrigerant:
Affix the warning sign “Warning: flammable ma-
terials” (W021 according to ISO7010) well vis-
ibly to the compressor. An adhesive label show-
ing this warning sign is enclosed with the Oper-
ating Instructions.
The combustion of refrigerant in the compressor’s ter-
minal box can only happen when several very rare er-
rors occur simultaneously. The probability of this event
occurring is extremely low. Combustion of fluorine-
based refrigerants can release lethal amounts of toxic
gases.
DANGER
Life-threatening exhaust gases and residues of
combustion!
Sufficiently ventilate the machinery room for at
least 2 hours.
Never inhale combustion products.
Use appropriate, acid-resistant gloves.
In case of suspected burnt refrigerant in the terminal
box of the compressor:
Do not enter the place of installation and ventilate it for
at least 2 hours. Do not enter the place of installation
until the combustion gases have completely escaped.
Never inhale combustion products. The potentially toxic
and corrosive exhaust air must be released into the at-
mosphere. It is necessary to use suitable, acid-resistant
gloves. Do not touch moist residues, but allow them to
dry, because they may contain dissolved toxic sub-
stances. Have trained staff clean the parts concerned
or, if the parts are corroded, dispose of them properly.
3.1.1
Compressor and refrigeration system
requirements
The specifications are established in standards (e.g.
EN378). In view of the high requirements and product
liability, it is generally advisable to conduct the risk as-
sessment in cooperation with a notified body. Depend-
ing on the design and the refrigerant charge, an as-
sessment according to the EU Framework Directives
2014/34/EU (ATEX 114) and 1999/92/EC (ATEX 137)
may be necessary.
DANGER
Fire hazard in the event of refrigerant leakage
and in the presence of an ignition source!
Avoid open fire and ignition sources in the ma-
chinery room and in the hazardous zone!
▶ Mind the ignition point in air of the refrigerant used,
see also EN378-1.
▶ Ventilate the machinery room according to EN378 or
install an extraction device.
▶ In case of leakage: Leaking refrigerant is heavier
than air and flows downwards. Avoid accumulation
and formation of ignitable blends with air. Do not in-
stall in ditches or near venting or drainage openings.
▶ The devices are not designed for operation in an Ex
zone. If it is not possible to avoid an ignitable atmo-
sphere by means of ventilation, the device has to be
shut down safely. The safety shut-down can be
triggered by a gas warning system that reacts at
20% of the LFL/LEL.
