6.10 Inputs and outputs
Different applications can be realised with the freely selectable inputs and outputs.
Output MFA and VA
Output MFA is a non-isolated relay output. Output VA is potential free.
All relay outputs can have a maximum loading of 3 A (AC1). The maximum total current
from all external loads must not exceed 4.5 A.
Setting parameters
13
,
14
,
15
Description
0
= forward reporting of operation (safety
valve LPG)
The contact closes as soon as heat demand is present or if the gas
supply is insufficient.
1
= Forward reporting of lockouts and warn-
ings
The contact closes as soon as a fault occurs or when a warning is
triggered for at least 4 minutes.
2
= external feeder pump
The output is activated in the same way as an internal heating circuit
pump (for heating and DHW).
3
= External heating circuit pump
The output is activated during heating operation.
4
= DHW load pump
The output is activated during DHW operation.
6
= DHW circulation pump via WCM-FS
The output is activated depending on the WCM-FS.
7
= Heating circuit pump via WCM-FS
Single unit (parameter
12
=
1
)
The output is activated when heating operation is requested by the
WCM-FS. When there is no longer a demand for heat, the pump runs
on for 3 minutes. The output is deactivated immediately DHW loading
is carried out (DHW priority).
Cascade (parameter
12
=
A
…
E
)
The output is activated by the cascade manager.
8
= Permanent voltage (only parameters
13
,
14
)
The output is permanently active.
9
= Flue gas damper (only parameter
13
)
The output is activated prior to burner start to open the flue gas damp-
er.
Input H1
Setting parameter
16
Description
0
= Release of heat exchanger in heating op-
eration
The release is given for heating operation when the input is closed.
The WTC is disabled for heating operations when the input is open.
1
= Heating circuit setback / normal
The normal setpoint is effective when the input is closed. The setback
value is effective when the input is open.
3
= Standby with frost protection
The system is in standby when the input is closed. The operating
modes DHW and heating are disabled. Frost protection is activated.
Systems with external WCM-FS or WCM-EM heating circuits are also
disabled.
4
= Return signal flue gas damper open
Burner start is only released once the flue gas damper is open and a
return signal has been sent to H1.
Input H2
Setting parameter
17
Description
0
= Release of heat exchanger in DHW op-
eration
The release for DHW is given when the input is closed. The WTC is
disabled for hot water operation when the input is open.
2
= Heating operation with special level
Installation and operating instruction
Gas condensing boiler WTC-GB 90-A
6 Operation
83266502 • 1/2010-08 • La
48-95
