9
GB 05/2009
AW HT
WATER CIRCUIT DATA
I A
Water content in the system
cPf
cQ
cdp
0
1
1
1
12%
0,985
1,02
1,07
20%
0,98
1,04
1,11
28%
0,974
1,075
1,18
35%
0,97
1,11
1,22
40%
0,965
1,14
1,24
Ethylene glycol solutions
Water and ethylene glycol solutions used as a heat carrier in
the place of water reduce the performance of the unit.
Multiply the performance figures by the values given in the
following table.
0
-5
-10
-15
-20
-25
Freezing point (°C)
Percentage of ethylene glycol by weight
cPf: correction factor refrigerating capacity
cQ: flow rate correction factor
cdp: pressure drop correction factor
f1: capacity correction factor
fk1: compressor power input correction factor
fx1: total power input correction factor
Fouling factors
The performance data given refer to conditions with clean
evaporator plates (fouling factor = 1).
For different fouling factors, multiply the figures in the perfor-
mance tables by the coefficient given in the following table.
4,4 x 10
-5
0,86 x 10
-4
1,72 x10
-4
-
0,96
0,93
-
0,99
0,98
-
0,99
0,98
Fouling factors
(m
2
°C/W)
f1
Evaporator
fk1
fx1
FILLING THE SYSTEM
- Before starting to fill, place the unit mains
switch QF1 in the OFF position.
- Before filling, check that the system drain
valve is
closed
.
- Open all system and terminal air vents.
- Open system shut off valves.
- Start filling by slowly opening the system water fill valve out-
side the unit.
- When water begins to leak out of the terminal air vent valves,
close them and continue filling until the pressure gauge indi-
cates a pressure of 1.5 bars.
The system must be filled
to a pressure of between 1
and 2 bars.
It is recommended
that this operation be repeated after
the unit has been operating for a number of hours. The
pressure should be checked regularly and if it drops
below 1 bar, the water content should be topped-up.
Check
the tightness of the joints.
EMPTYING THE SYSTEM
- Before starting to empty, place switch QF1
in the
OFF
position
- Make sure the system fill/top-up water
valve is closed.
- Open the drain cock outside the unit and
all the installation and terminal air vent
valves..
If the fluid in the circuit
contains antifreeze, it should
not be allowed to drain freely, as it is pollutant.
It should be collected for possible reuse.
When draining after heat pump operation, take care as
the water may be hot (up to 50°).
ON
OFF
ON
OFF
Size
0031 0041 0061 0071
Minimum water content
l
75
105
130
175
Size
0031 0041 0061 0071
Expansion vessel volume
l
4
5
5
8
