SystemAir AC-RSR105R32HEC, Installation And Maintenance Manual

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5 SYSAER R32
Machinery rooms shall have doors opening outward and sufficient in number to ensure persons can escape
in an emergency.
²
The doors shall be tight fitting and self-closing. They shall be so designed that they can be
opened from inside (anti-panic system). The doors shall have at least a one-hour fire resistance
construction, using materials and construction tested in accordance with EN 1634. There shall be
no openings that permit unintended passage of escaping refrigerant, vapours, odours and all other
gases to any occupied space.
²
Provision
shall be made to facilitate immediate exit from the machinery room in the event of
an emergency. At least one emergency exit shall open directly to the open air or it shall lead to an
emergency exit passageway.
²
Service ducts shall conform to the requirements of EN 1366-1 and EN 1366-2, and they shall
be sealed to minimize escaped refrigerant leakage into the service duct, and shall have at least the
same fire resistance as walls and doors.
²
Service ducts
, including walkways and crawl spaces, containing piping for refrigerants shall be
vented to a safe place to prevent a dangerous accumulation of refrigerant in the event of a leak.
Service ducts shall not be used for ventilation or conditioned air.
²
Sheet metal for normal and emergency ventilation ducts shall be in accordance with EN 1507
and supported as required by EN 12236. After erection all duct seams and joints shall be sealed to
minimize gas leakage from the duct. The ventilation duct shall have at least the same fire resistance
as the doors and walls of the machinery room.
²
Ventilation
: The ventilation of machinery rooms shall be sufficient both for normal operating
conditions and emergencies. Air from machinery rooms shall be vented outdoors using mechanical
ventilation in case of a release of refrigerant due to leaks of components. This ventilation system
shall be independent of any other ventilation system on the site.
Provision shall be made for a sufficient supply of outside replacement air and a good distribution of
that air over the machinery room avoiding dead zones.
Openings for outside air shall be positioned to avoid re-circulation into the room.
Ventilation for normal operating conditions or when machinery room is occupied
Ventilation shall be in accordance with national regulations with a minimum of 4 air changes
per hour when the machinery room is occupied. In the event that the necessary ventilation
rate cannot be achieved an audible and/or visual alarm shall be initiated and, where relevant,
electrical supplies shall be terminated.
Emergency mechanical ventilation
If gas detection is required in the machinery room, the emergency mechanical ventilation
system shall be activated by a detector(s), located in the machinery room.
Emergency mechanical ventilation shall be provided with two independent emergency
controls one located outside the machinery room, and the other inside.
Required airflow for emergency mechanical ventilation
Airflow of the mechanical ventilation shall be at least the quantity obtained by Formula (1):
Where
V ̇ = 0,014xm
2/3
- V ̇ is the air flow rate in m
3
/s;
- m is the mass of refrigerant charge, in kg, in the refrigerating system with the largest
charge, any part of which is located in the machinery room;
- 0,014 is a conversion factor with units of m
3
/s kg
2/3
.
An emergency ventilation system with 15 air changes per hour is sufficient
Mechanical ventilation openings
Mechanical ventilation openings shall be made in the position and of sizes to permit
sufficient airflow considering the characteristics of the refrigerant, the choice of intake or
exhaust and the performance of the ventilator. The intake and exhaust openings shall be
arranged to evacuate the refrigerant under all conditions of leaking refrigerant