23
EN
G
LIS
H
Freeze protection
Frost can make some damage on the hydraulic system. It is because it is installed outside house nomally. To avoid taking risks
of freezing problem, special cares such as Anti-freezing fluid are required as below. Ethylene glycol concentration can vary
depeding on outdoor temperature where our system is installed, fill in Ethylene glycol by mixing as below.
Ethylene Glycol Is Toxic
Ethylene glycol is toxic if swallowed, and therefore is a hazard to animals and small children.
Ethylene glycol must be handled in accordance with relevant local laws and regulations.
WARNING
Outdoor temperature
Ethylene Glycol(%)
23°F (–5°C)
10
14°F (–10°C)
20
5°F (–15°C)
25
–10°F (–20°C)
35
Setting capacity and pre-pressure of the expansion vessel
When it is required to change the default pre-pressure of
the expansion vessel(1 bar), keep in mind the following
guidelines:
f
Use only dry nitrogen to set the expansion vessel pre-
pressure.
f
Inappropriate setting of the expansion vessel
pre-pressure will lead to malfunction of the system.
Therefore, the pre-pressure should only be adjusted by a
licensed installer.
2.5
2.0
1.5
1.0
0.5
0.0
150
200
250
300
350
Total water volume(ℓ)
Pr
e-
pr
es
su
re
(b
ar
)
Operation range
Installation height
difference(a)
Water volume
< 220 Litres
> 220 Litres
<7m
No pre-pressure adjustment required.
Actions required:
•
Pre-pressure must be decreased, calculate
according to “Calculating the pre-pressure of
the expansion vessel”.
•
Check if the water volume is lower than
maximum allowed water volume.
>7m
Actions required:
•
Pre-pressure must be increased, calculate the
appropriate value following by “Calculating
the pre-pressure of the expansion vessel”.
•
Check if the water volume is lower than
maximum allowed water volume.
Expansion vessel of the unit too small for the
installation.
(a) Installation height difference: height difference(m) between the highest point of the water circuit and the indoor unit. If
the unit is located at the highest point of the installation, the installation height is considered 0m.
Calculating the pre-pressure of the expansion vessel
f
The pre-pressure(Pg) to be set depends on the maximum installation height difference(H) and is calculated as below :
Pg=(H/10+0.3) bar
EHS mono_RC＊＊＊MHXGA_IM_E_34411A(3).indd 23
2012-11-26 오후 3:01:59
