Configuring The Dual Mode Point; Configuration Example; Diagram For Calculating The Dual Mode Point And The Output Of The Electric Immersion Heater - Wolf BWL-1S-05 Installation And Operating Instructions Manual

32 Configuring the dual mode point
32.1 Configuration example
Central heating demand (building heat load) to DIN 4701 or EN 12831 of 7.7 kW. A DHW demand for 4 people
(0.25 kW/person) and a standard outside temperature of -16 °C are assumed.
The power supply utility specifies a blocking time of 2 x 2 hours. The blocking time factor Z is 1.1.
Using these figures, the required heat pump output is calculated as follows:
.
Q
HP
.
Q
E-rod
.
Q
.
HP
Q
.
G
Q
.
DHW
Q
.
E-rod
Q
HP,Tn
Z
32.2 Diagram for calculating the dual mode point and the output of the
electric immersion heater
.
Q
HP
6
.
Q
E-rod
.
Q
HP,Tn
Standard outside temperature
Standard outside temperature
1
2
Required peak output of the heat pump system Q
Heat demand of the building up to the heating limit pressure
3
Dual mode point (= point where the heat demand of the building intersects with the max. compressor speed)
4
Proportion of heat pump heating output at standard outside temperature
5
Proportion of electric immersion heater heating output at standard outside temperature
6
90
Configuring the dual mode point
.
.
= (Q + Q ) x Z =
G DHW
. .
= Q - Q =
HP HP,Tn
:
Required peak output of the heat pump system
:
Building heat load (building heat demand, heating energy demand)
:
Output demand for DHW heating
:
Immersion heater output
:
Heating output of heat pump for standard design point
:
Blocking time factor
30
25
20
15
10
2
9.6
5
5
4.7
0
-20 -15 -10
1
-16
6
5
4
3
2
1
0
-20 -15 -10
10
8
6
(7.7 kW + 1.0 kW) x 1.1 = 9.6 kW
9.6 kW - 4.7 kW = 4.9 kW
3
4
-5 0 5 10
-6
Dual mode point Heating limit temperature
HP
-5 0 5 10
Max. compressor speed
Min. compressor speed
15 20 25 30 35
Air intake temperature [°C]
15 20 25 30 35
30
25
20
15
10
5
0
-20 -15 -
6
5
4
3
2
1
0
-20 -15 -
10
8
6
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