Daikin EWWT100Q - 1.1. Information about Installation of Systems with R32

D-EIMHP01702-23_00EN- 15/72
1.1. Information about installation of systems with R32
Physical characteristics of R32 refrigerant
Safety class (ISO 817)
A2L
PED Group
1
Practical limit (kg/m
3
)
0.061
ATEL/ ODL (kg/m
3
)
0.30
LFL (kg/m
3
) @ 60°C
0.307
Vapour density @25°C, 101.3 kPa (kg/m
3
)
2.13
Molecular mass
52.0
Boiling point (° C)
-52
GWP (100 yr ITH)
675
GWP (ARS 100 yr ITH)
677
Autoignition temperature (° C)
648
The chiller has to be installed in open air or machinery room (location classification III).
To ensure location classification III a mechanical vent on the secondary circuit(s) has to be installed.
Local building codes and safety standards shall be followed; in absence of local codes and standards refer to EN 378-3:2016 as a
guide.
In paragraph “Additional guidelines for safe use of R32” there are provided additional information that should be added to th e
requirements of safety standards and building codes.
Additional guidelines for safe use of R32 for equipment located in the open air.
Refrigerating systems sited in the open air shall be positioned to avoid leaked refrigerant flowing into a building or otherwise
endangering people and property.
The refrigerant shall not be able to flow into any ventilation fresh air opening, doorway, trap door or similar opening in the event of a
leak. Where a shelter is provided for refrigerating equipment sited in the open air it shall have natural or forced ventilation.
For refrigeration systems installed outside in a location where a release of refrigerant can stagnate e.g., below ground, then the
installation shall comply with the requirements for gas detection and ventilation of machinery rooms.
Additional guidelines for safe use of R32 for equipment located in a machinery room.
When a machinery room is chosen for the location of the refrigerating equipment it shall be in accordance with local and national
regulations. The following requirements (according to EN 378-3:2016) can be used for the assessment.
• A risk analysis based on the safety principle for a refrigeration system (as determined by the manufacturer and including
the charge and safety classification of the used refrigerant) should be conducted to determine if it is necessary to install
the chiller in a separate refrigeration machinery room.
• Machinery rooms should not be used as occupied spaces. The building owner or user shall ensure that access is
permitted only by qualified and trained personnel doing the necessary maintenance to the machinery room or general
plant.
• Machinery rooms shall not be used for storage except for tools, spare parts, and compressor oil for the installed
equipment. Any refrigerants, or flammable or toxic materials shall be stored as required by national regulations.
• Open (naked) flames shall not be permitted in machinery rooms, except for welding, brazing or similar activity and then
only provided the refrigerant concentration is monitored and adequate ventilation is ensured. Such open flames shall
not be left unattended.
• A remote switching (emergency type) for stopping the refrigerating system shall be provided outside the room (near
the door). A similar acting switch shall be located at a suitable location inside the room.
• All piping and ducting passing through floors, ceiling and walls of machinery room shall be sealed.
• Hot surfaces shall not exceed a temperature of 80 % of the auto-ignition temperature (in °C) or 100 K less than the
auto-ignition temperature of the refrigerant, whichever is lower.
Refrigerant
Self-ignition temperature
Maximum surface temperature
R32
648 °C
548°C
• Machinery rooms shall have doors opening outward and sufficient in number to ensure freedom for persons to escape
in an emergency; the doors shall be tight fitting, self-closing and so designed that they can be opened from inside
(antipanic system).
• Special machinery rooms where the refrigerant charge is above the practical limit for the volume of the room shall have
a door that either opens directly to the outside air or through a dedicated vestibule equipped with self-closing, tight-
fitting doors.
• The ventilation of machinery rooms shall be sufficient both for normal operating conditions and emergencies.
• Ventilation for normal operating conditions shall be in accordance with national regulations.
• The emergency mechanical ventilation system shall be activated by a detector(s), located in the machinery room.
o This ventilation system must be:
▪ independent of any other ventilation system on the site.
▪ provided with two independent emergency controls one located outside the machinery room, and the other
inside.
o The emergency exhaust ventilation fan shall: