N = N pump
D = L pump
= PE pump
Caution
If the neutral position of the three-way valve is adjusted with pa
rameter
, the pump must be connected as follows:
N = N pump
C = L pomp
= PE pump
Control of external gas valve (EgV)
If there is a heat demand, an alternating voltage of 230 VAC, 1 A (maxi
mum) becomes available on the EgV terminals of the connector to control
an external gas valve.
Connecting the minimum gas pressure switch (Gps)
The minimum gas pressure switch blocks the boiler if the gas inlet pres
sure becomes too low.
1. Connect the minimum gas pressure switch to the Gps terminals of
the connector.
The presence of the gas pressure switch must be set using parameter
.
Connecting a heat recovery unit (Hru)
1. Connect the wires from the heat recovery unit to the Hru terminals of
the connector.
The presence of the heat recovery unit must be set using parameter
.
Operation signal and error message (status)
You can choose between an alarm or operation signal using parameter
.
If the boiler is in operation, the operating message can be connected via
a potential-free contact (maximum 230 VAC, 1 A) to terminals Noand
Cof the terminal connector.
If the boiler locks out, the alarm can be relayed via a potential-free con
tact (maximum 230 VAC, 1 A) to terminals Ncand Cof the terminal con
nector.
Connection options for the PCB (SCU-X01)
The SCU-X01 PCB has two potential-free contacts (status), which can be
configured as required. Depending on the setting, a maximum of two mes
sages about the status of the boiler can be transmitted. See table. Select
the messages required using rotary knobs SW1 and SW2. Use rotary
knob SW1 for messages on the status connector X3. Use rotary knob
SW2 for messages on the status connector X4.
Tab.25 Configuring the rotary knobs
Position
C-NO
C-NC
0
Alarm standby
Alarm active
1
Alarm inverted active
Alarm inverted standby
2
Burning standby
Burning active
3
Burning inverted active
Burning inverted standby
4
Burning low standby
Burning low active
5
Burning high standby
Burning high active
Fig.35
SCU-X01 PCB
AD-0000059-01
SCU-X01
X2
X2a
X4
Status
C
Nc
No
C
Nc
No
X3
Status
C
Nc
No
C
Nc
No
SW2
SW1
6 Installation
40
123157 - v.12 - 07022018
