Circuits
CIRCA0
(EHC–05)
DHW
(EHC–05)
CIRCA1
(SCB-10)
CIRCB1
(SCB-10)
CIRCC1
(with
AD249 op
tion)
CIR
CAUX1
(with
AD249 op
tion)
DHW1
(SCB-10)
Buffer tank for storage
X
Deactivation
X
X
X
X
X
X
X
(1) Use the direct zone underfloor heating option
Description of the EHC–05 PCB
X1 Main power supply for the 230 V - 50 Hz indoor module
X4
Hydraulic version: Hydraulic back-up pump
Electrical version: Electrical back-up - stage 1
X5
Hydraulic version: Hydraulic back-up ON/OFF contact
Electrical version: Electrical back-up - stage 2
X7 Local communication bus to the SCB-10 PCB
X8 Control panel display for the indoor module
X9 Sensors
X10 Speed control signal for the heat pump circulating pump
X12 Options
R-Bus: Baxi uSense connected room thermostat, on/off
thermostat, modulating thermostat or OpenTherm thermostat for
the CIRCA0 direct zone
BL1 / BL2: multifunction inputs
So+/So- : Electric energy meter
Condensation: condensation sensor
X15 Not used
X16 Not used
X17 Not used
X18 Input/output for the HPC–01 PCB
X19 Control signal for the immersion heater on the domestic hot water
tank
X22 Bus for communication with the outdoor unit HPC–01 PCB
X23 Bus for communicating with the outdoor unit
X24 Not used
X25 Heating reversing valve: CIRCA0 /Domestic hot water: DHW
X26 CIRCA0 direct heating circuit pump
X27 Heat pump circulating pump power supply
X28 Temperature sensor:
T dhw 1: Temperature sensor at the bottom of the DHW
domestic hot water tank (optional)
T dhw 2: Temperature sensor at the top of the DHW tank
T out: not used
Fig.38
MW-1001169-4
R-Bus
T dhw 1
T dhw 2
T out
BL1 IN
BL2 IN
So+ So-
Condensation
X15
X26
X2
X25
X13 X6
X21
X24
X12
X9
X4
X5
X19
X17
X16
X10
X23
X30
X18
X1
X20
X7 X8
X27
X22
}
X28
}
So
-
+
6 Installation
7762758 - v05 - 19082020
39