5.13 Configuring the hybrid operating mode of a hydraulic back-up
The hybrid function consists of an automatic switch between the heat
pump and the boiler, according to the cost, the consumption or emission of
CO
2
of each heat generator.
Tab.35 Calculating the threshold coefficient of performance
If the coefficient of performance of the heat pump is higher than the threshold coefficient of performance, the heat pump takes
priority. Otherwise only the boiler back-up is enabled. The heat pump coefficient of performance depends on the outside
temperature and the heating water set point temperature.
Hybrid mode
(HP061) parame
ter
Description
HP061 = Hybrid
Cost
Optimisation of energy costs for the consumer (factory setting): the control system chooses the cheapest
generator according to the coefficient of performance of the heat pump and according to energy cost.
The switch between the heat pump and the boiler occurs at the value of the threshold coefficient of per
formance calculated according to energy cost optimisation mode with the energy cost parameters.
Peak elec. cost (HP062): Peak rate cost of electricity
Off-peak elec. cost (HP063): Off-peak rate cost of electricity
Gas or oil cost (HP064): Cost of fossil energy (oil or gas) – price per m
3
or per litre – Can be set from
0.01 to 2.50 €/kWh
HP061 = Primary
Energy
Optimisation of primary energy consumption: The control system chooses the generator that consumes the
least primary energy.
The switch between the heat pump and the boiler occurs at the value of the coefficient of performance
threshold COP Threshold (HP054) according to the primary energy consumption optimisation mode.
HP061 = Hybrid
CO2
Optimisation of CO
2
emissions: The control system chooses the generator that emits the least CO
2
.
The switch between the heat pump and the boiler occurs at the threshold coefficient of performance value
calculated according to the CO
2
emissions optimisation mode:
CO2 coef. elec. CH (HP065): Electricity CO
2
emissions in heating mode
CO2 coef. elec. DHW (HP066): Electricity CO
2
emissions in domestic hot water production mode
CO2 coef. of gas/oil (HP067: Gas or oil CO
2
emissions)
HP061 =No
Hybrid
No optimisation: The heat pump always starts up first, regardless of the conditions. The boiler back-up
starts up afterwards, if necessary.
Influence of outdoor temperatures and bi-valency
C COP: Coefficient of performance
C
S
Threshold coefficient of performance
T Outdoor temperature
T
1
Min. Outdoor T. HP (HP051) parameter: Minimum outdoor
temperature for the heat pump to stop
T
2
Bivalent temperature (HP000) parameter: Bi-valency outdoor
temperature
Fig.29
+
T
1
T
2
T
C
C
S
+
T
1
T
2
T
C
C
S
T
1
T
2
T
C
C
S
MW-5000542-1
5 Operation
40
200 ESL HYBRID
7763552 - v02 - 29062020
