Installation manual
17
EKHBH/X008BB
Indoor unit for air to water heat pump system
4PW62570-1A – 01.2011
3
Using the table and instructions below, determine if the total
water volume in the installation is below the maximum allowed
water volume.
Calculating the pre-pressure of the expansion vessel
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
Checking the maximum allowed water volume
To determine the maximum allowed water volume in the entire circuit,
proceed as follows:
1
Determine for the calculated pre-pressure (Pg) the
corresponding maximum water volume using the graph below.
2
Check that the total water volume in the entire water circuit is
lower than this value.
If this is not the case, the expansion vessel inside the indoor unit is
too small for the installation.
Example 1
The indoor unit is installed 5 m below the highest point in the water
circuit. The total water volume in the water circuit is 100 l.
In this example, no action or adjustment is required.
Example 2
The indoor unit is installed at the highest point in the water circuit.
The total water volume in the water circuit is 350 l.
Result:
■
Since 350 l is higher than 280 l, the pre-pressure must be
decreased (see table above).
■
The required pre-pressure is:
Pg = (H/10 + 0.3) bar = (0/10 + 0.3) bar = 0.3 bar
■
The corresponding maximum water volume can be read from
the graph: approximately 410 l.
■
Since the total water volume (350 l) is below the maximum water
volume (410 l), the expansion vessel suffices for the installation.
Setting the 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:
■
Use only dry nitrogen to set the expansion vessel pre-pressure.
■
Inappropriate setting of the expansion vessel pre-pressure will
lead to malfunction of the system. Therefore, the pre-pressure
should only be adjusted by an installer.
Connecting the water circuit
Water connections must be made in accordance with the applicable
legislation and the outlook diagram delivered with the unit, respecting
the water in- and outlet.
6.9.
Charging water
1
Connect the water supply to a drain and fill valve (see
2
Make sure the automatic air purge valve is open (at least 2
turns).
3
Fill with water until the manometer indicates a pressure of
approximately 2.0 bar. Remove air in the circuit as much as
possible using the air purge valves. Air present in the water
circuit might cause malfunctioning of the backup heater.
4
Check that the backup heater vessel is filled with water by
opening the pressure relief valve. Water must flow out of the
valve.
Installation
height
difference
(a)
(a) Installation height difference: height difference (m) between the highest point of
the water circuit and the indoor unit. If the indoor unit is located at the highest
point of the installation, the installation height is considered 0 m.
Water volume
≤
280 l
>280 l
≤
7 m
No pre-pressure adjustment
required.
Actions required:
• pre-pressure must be
decreased, calculate
according to
pre-pressure of the
expansion vessel"
• check if the water volume is
lower than maximum allowed
water volume (use graph
below)
>7 m
Actions required:
• pre-pressure must be
increased, calculate
according to
pre-pressure of the
expansion vessel"
• check if the water volume is
lower than maximum allowed
water volume (use graph
below)
Expansion vessel of the unit
too small for the installation.
pre-pressure
= pre-pressure
maximum water volume
= maximum water volume
0.3
0.5
1
1.5
2
2.5
100
50
0
10
150
200
250
300
350
400
450
maximum water volume [l]
pre-pressure [bar]
NOTICE
Be careful not to deform the unit piping by using excessive
force when connecting the piping. Deformation of the
piping can cause the unit to malfunction.
INFORMATION
■
During filling, it might not be possible to remove all air
in the system. Remaining air will be removed through
the automatic air purge valves during first operating
hours of the system. Additional filling with water
afterwards might be required.
■
The water pressure indicated on the manometer will
vary depending on the water temperature (higher
pressure at higher water temperature).
However, at all times water pressure should remain
above 0.3 bar to avoid air entering the circuit.
■
The unit might dispose some excessive water through
the pressure relief valve.
■
Water quality must be according to EU directive 98/
83 EC.
