EKHBRD011~0Y17
Indoor unit for air to water heat pump system
4P402191-1B – 2017.09
Installation manual
6
Design of the hydraulic system
When designing the hydraulic system, always consult
application examples" on page 2
for references.
When designing the hydraulic system always consider the available
external static pressure of the EKHBRD* unit.
The pump will adjust its rpm (rotations per minute) as to control a
fixed
∆
T between return and leaving water temperature.
This external static pressure-graph is valid at maximum pump rpm.
Simultaneous operation of the auxiliary boiler and the
EKHBRD* unit is
NOT allowed
.
Pay special attention to the control of the circulation
pump of the auxiliary boiler. This pump should not
operate simultaneously with the EKHBRD* unit.
A simultaneous operation of both systems will risk the
plate heat exchanger of the EKHBRD* unit to freeze-
up!
External static pressure (kPa)
Flow (l/min)
Without 3-way valve
Including 3-way valve
Maximum external static pressure if
∆
T = 10°C
Maximum external static pressure if
∆
T = 5°C
10
20
30
40
50
60
70
80
0
19
17
15
21 23 25 27 29 31 33 35 37 39 41 43 45 47
flow [l/min]
ESP
[kP
a
]
90
100
16 kW
14 kW
14 kW
11 kW
11 kW
16 kW
NOTE
When replacing an old gas or fuel oil boiler by a air to
water heat pump system (EKHBRD*):
■
please always check the specifications of the
pump of the old unit;
■
if the external static pressure of that pump is
higher than the external static pressure of the air
to water heat pump system, please install an
additional pump with higher external static
pressure in combination with a balancing bottle.
Example of a high external static pressure system
3
4
2
1
1
Air to water heat pump system (EKHBRD*)
2
Balancing bottle
3
High external static pressure pump (field supply)
4
High external static pressure system
3
3
4
5 6
2
1
8
7
10
11
A
B
9
12 13
13
13
C
C1
1
Outdoor unit
2
Indoor unit
3
Electronic expansion valve
4
Refrigerant heat exchanger
5
Water heat exchanger
6
Pump
7
Compressor
8
Balancing bottle (field supply)
9
Pump (field supply)
10
Collector (field supply)
11
By-pass valve (field supply)
12
Shut off valve (field supply)
13
Radiator (field supply)
C1
Remote controller
A
Installation place
B
Living room
C
Example of a high static pressure system:
radiators installed in series or very small piping
4PEN402191-1B_2017_09.book Page 6 Friday, October 6, 2017 7:03 PM
