Calculating The Density Limit - Panasonic PAW-160MAH2L Installation Instructions Manual

General information and safety instructions
WARNING
The following precautions need to be followed strictly, in order to avoid hazardous situations,
which could result in death or serious injury.
A fi re or explosion hazard and the generation of poisonous gas may result if R32 refrige-
rant gas comes into contact with open fl ames.
► The air conditioning appliance with direct expansion (DX) coil shall be installed, ope-
rated and stored in a space without continuously operating ignition sources (e.g. open
fl ames, an operating gas appliance or an operating electric heater).
► If DX coil appliance is not installed in a separate refrigeration machinery room as spe-
cifi ed in EN378, calculate the maximum allowed density limit of the relevant installati-
on space as detailed below (see → 1.4.1 Calculating the density limit).
► The DX coil appliance shall be installed, operated and stored in a well ventilated space
with a ceiling height of at least 2.5 m and a fl oor area larger than [A
complies with the required density limit (see → 1.4.1 Calculating the density limit).
► Pay particular attention to prevent refrigerant leakages during installation, mainte-
nance and repair work (see → 1.4.2 Preventing leaks).
► If a leak is suspected, do the following:
► Repair any leaks diligently (see → 1.4.4 Repairing leaks), before refi lling the refrige-
rant cycle with refrigerant and checking for any leaks again.
!
NOTICE
For full details on the required precautions for the installation and maintenance of an R32 unit,
always refer to the Installation Guide of the relevant PACi unit.

1.4.1 Calculating the density limit

As R32 is a slightly fl ammable refrigerant (ASHRAE fl ammability class A2L), the requirements
for the installation space of the DX coil appliance must comply with the applicable regulations
and standards, such as EN60335-2-40 and EN378.
Depending on perspective, the density limit determines either the minimum fl oor area "A
(specifi ed in m
the allowed maximum refrigerant charge "m
relation to the fl oor area of the available installation space (specifi ed in m
R32 installations (based on EN60335-2-40, 5th edition) also depend on the mounting position of
the DX coil.
10
» remove or extinguish all naked fl ames immediately
» ventilate the room immediately
» use a calibrated electronic leak dectector to detect any leaks (see
→ 1.4.3 Detecting leaks)
) required for a given refrigerant charge amount (specifi ed in kg), or vice versa
2
" for the DX coil appliance (specifi ed in kg) in
max
] m so that it
2
min
"
min
). The charge limits for
2