Daikin EBHQ011BA6V3, Руководство по установке

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Installation manual
15
E(D/B)(H/L)Q011~0W1
Unit for air to water heat pump system
4PW57621-1A
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.
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
(bar)
=(H
(m)
/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 unit is too small
for the installation.
figure "Maximum allowed water volume"
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 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
(bar)
= (H
(m)
/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 a licensed installer.
NOTE
When circulation in each space heating loop is
controlled by remotely controlled valves, it is important
that this minimum water volume is kept even if all the
valves are closed.
Example
1 Unit FHL1..3 Floor heating loop
(field supply)
2 Heat exchanger
3 Pump T1..3 Individual room
thermostat (optional)
4 Shut-off valve
5 Collector (field
supply) M1..3 Individual motorised
valve to control loop
FHL1 (field supply)
6 By-pass valve
(field supply)
I User interface
Installation
height
difference
(a)
(a) Installation height difference: height difference (ft)(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.
Water volume
≤
280 l
>280 l
≤
7 m
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
(use graph below)
>7 m
Actions required:
• pre-pressure must be increased,
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.
FHL1
FHL2
FHL3
M1
T1
M2
T2
M3
T3
3 2 1 5 6
I
4
= pre-pressure
= maximum water volume
A = System without glycol
B = System with 25% propylene glycol
(Refer to "Caution: "Use of glycol"" on page 16 )
0.3
0.5
1
1.5
2
2.5
100 50 0 20 150 200 250 300 350 400 450
[l]
maximum water volume
[bar]
pre-pressure
B A