EAS ELECTRIC ETHKH160 Manual De Instrucciones página 69

2. Using the table below, determine if the expansion vessel
pre- pressure requires adjustment.
3. Using the table and instructions below, determine if the total
water volume in the installation is below the maximum allowed
water volume.
Installation
Water volume
height
≤160 L
(a)
difference
No pre-pressure adjustment
≤7 m
required.
Actions required:
• pre-pressure must be increased,
calculate according to "Calculating
the pre-pressure of the expansion
>7 m
vessel"
• check if the water volume is lower
than maximum allowed water
volume (use graph below)
(a) Installation height difference: height difference (m) between the
highest point of the water circuit and the unit. If the unit is located
at the highest point of the installation, the installation height is
considered 0 m.
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(m)/10 + 0.3 bar(g)
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 unit is too small
for the installation.
2.8
2.3
1.8
1.3
A2
0.8
B2
0.3
0 50 100
Maximum water volume [L]
maximum water volume
pre-pressure = pre-pressure
maximum water volume = maximum water
volume
A1 System without glycol for ETH-KH160 units
B1 System with 25% propylene glycol for ETH-KH160 and units
(Refer to "Caution: "Use of glycol")
>160 L
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 (use graph below)
Expansion vessel of the unit too
small for the installation.
A1
B1
150 200 250
Example 1
The 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 unit is installed at the highest point in the water circuit. The total
water volume in the water circuit is 180 L.
Result:
■ Since 180 L is higher than 160 L, the pre-pressure must be
decreased (see table above).
■ The required pre-pressure is:
Pg = H(m)/10+0.3 = 0/10+0.3 = 0.3 bar(g)
■ The corresponding maximum water volume can be read from the
graph: approximately 210 L.
■ Since the total water volume (180 L) is below the maximum water
volume (210 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(g)], 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 a licensed installer.
Connecting the water circuit
Water connections must be made in accordance with the outlook
diagram delivered with the unit, respecting the water in- and outlet.
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.
If air, moisture or dust gets in the water circuit, problems may occur.
Therefore, always take into account the following when connecting
the water circuit:
■ Use clean pipes only.
■ Hold the pipe end downwards when removing burrs
■ Cover the pipe end when inserting it through a wall so that no dust
and dirt enter.
■ Use a good thread sealant for the sealing of the connections.
The sealing must be able to withstand the pressures and
temperatures of the system.
■ When using non-brass metallic piping,make sure to insulate both
materials from each other to prevent galvanic corrosion.
17
V.1