Daikin EPRA08EAV3, Installer'S Reference Manual

Page: 210 / 292

10 | Configuration
Installer reference guide
210
EPRA08~W1 + ETVH/9W
Daikin Altherma 3 H MT F
4P634886-1 – 2021.03
b Auxiliary boiler inactive
If the outdoor
temperature…
Then…
Space heating by the heat
pump system…
Bivalent signal for the
auxiliary boiler is…
Drops below T
calc
Stops Active
Rises above T
calc
+3°C Starts Inactive
INFORMATION
The permission signal for the auxiliary boiler is located on the EKRP1HBAA (digital I/O
PCB). When it is activated, the contact X1, X2 is closed and open when it is
deactivated. See illustration below for the schematic location of this contact.
YC Y1 Y2 Y3 Y4
X1
X2
X3
X4
OFF ON
X2M
SS1
X1M
# Code Description
9.C.3 [C-03] Range: –25°C~25°C (step: 1°C)
9.C.4 [C-04] Range: 2°C~10°C (step: 1°C)
The higher the value of [C‑04], the higher the
accuracy of the switch-over between the heat
pump system and the auxiliary boiler.
To determine the value of [C‑03], proceed as follows:
1 Determine the COP (= coefficient of performance) using the formula:
Formula Example
COP = (Electricity price / gas price)
(a)
×
boiler efficiency
If:
▪ Electricity price: 20 c€/kWh
▪ Gas price: 6 c€/kWh
▪ Boiler efficiency: 0.9
Then: COP = (20/6)×0.9 = 3
(a)
Make sure to use the same units of measurement for the electricity price and gas price
(example: both c€/kWh).
2 Determine the value of [C‑03] using the graph. For an example, see the table
legend.