Rotex Controller Series, Product Documentation

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EbV Product documentation THETA NORM/UNIT
7-2
7.1.3 Heating Circuit Outside Temperature Assignment (Outdoor Sensor 2)
NOTE: Function active only when using a second outdoor sensor!
Function: If a second outdoor sensor (OS2) is connected to a variable input in the central unit, the
heating circuit can be assigned either to external sensor 1, 2 or to the mean value of
both sensors.
The following applies to each external sensor:
In case of a defect of one of the sensors, there is an automatic switchover to the
remaining outdoor sensor and a simultaneous malfunction message. In case of a defect
affecting both sensors, the heating circuit is regulated on the basis of a set heating curve
and heating program corre-sponding to a fictitious external temperature of 0 °C with
regard to the set minimum temperature.
7.1.4 Alternative connection of the outdoor sensor to the boiler control (..C..)
Function: Condensing boilers with MCBA boiler controls have a connection for an outdoor sensor
by Honeywell. For more information, see "Features of fuel value heat generator via data
bus (MCBA) (..C..)", Page 8-16.
7.1.5 Error display outdoor sensor during MCBA operation
MCBA-boiler controls also use the AF-input for switching off the heating system. A
sensor short circuit is defined as "heating system off".
If an MCBA is used as an H-GEN and a short circuit is registered at the OS input of the
MCBA, the notice "heating system OFF" is displayed instead of the OS short circuit.
7.1.6 Evaluation of the sensor errors MCBA
The controller displays a sensor error when the MCBA is blocked. Only the error
message blocked with the corresponding number should be displayed (e.g. E41).
• If the sensor is connected to the MCBA, sensor errors are not sent via the data bus.
The evaluation is carried out logically in THETA.
• If the MCBA is blocked, the activation of a sensor error in THETA must be
surpressed.
Operation:
Note on operation Key / parametertree Parameter
Set to OS 2
HYDRAULIC PARAMETER 08
or
PARAMETER 09
or
PARAMETER 10
Assignment unmixed circuit
UNMIXED CIRCUIT PARAMETER 10
Assignment mixed circuit 1
MIX.VALVE-1 PARAMETER 10
Assignment mixed circuit 2
MIX.VALVE-2 PARAMETER 10