Daikin Altherma 3 HT - Page 48

6 | Application guidelines
Installer reference guide
48
EPRA14~18D + ETVH/X16S18+23E
Daikin Altherma 3 H HT F
4P644737-1A – 2022.03
a Dedicated Human Comfort Interface (BRC1HHDA used as room thermostat)
b Non-return valve (field supply)
c Shut-off valve (field supply)
d Auxiliary boiler (field supply)
e Aquastat valve (field supply)
NOTICE
▪ Make sure the auxiliary boiler and its integration in the system complies with
applicable legislation.
▪ Daikin is NOT responsible for incorrect or unsafe situations in the auxiliary boiler
system.
▪ Make sure the return water to the heatpump does NOT exceed 70°C. To do so:
- Set the desired water temperature via the auxiliary boiler controller to
maximum 70°C.
- Install an aquastat valve in the return water flow of the heat pump. Set the
aquastat valve to close above 70°C and to open below 70°C.
▪ Install non-return valves.
▪ An expansion vessel is already pre-mounted in the indoor unit. But for bivalent
operation, also make sure that there is an expansion vessel in the auxiliary boiler
loop. Otherwise when bivalent operation is running and if the Aquastat valve
would close, there would be no expansion vessel in the water circuit anymore.
▪ Install the digital I/O PCB (option EKRP1HBAA).
▪ Connect X1 and X2 (changeover to external heat source) on the digital I/O PCB to
the auxiliary boiler. See "9.3.8 To connect the changeover to external heat
source"[4122].
▪ To setup the heat emitters, see "6.2 Setting up the space heating/cooling
system"[433].
Configuration
Via the user interface (configuration wizard):
▪ Set the use of a bivalent system as external heat source.
▪ Set the bivalent temperature and hysteresis.
Changeover to external heat source decided by an auxiliary contact
▪ Only possible in external room thermostat control AND one leaving water
temperature zone (see "6.2Setting up the space heating/cooling system"[433]).
▪ The auxiliary contact can be:
- An outdoor temperature thermostat
- An electricity tariff contact
- A manually operated contact
- …
▪ Setup: Connect the following field wiring:
L
N
H Com
A
K2AK1A
X2M
B
TI
K2AK1A
Indoor/Auto/Boiler
35 30 X Y
Indoor