en
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Installation
Indications,
functions and options
Messages
Commissioning
Operation and function
System-specific functions
The following adjustments are used for the specific functions in system 8.
∆
T control for the backup heating by a solid fuel boiler
DT3O
Switch-on temperature difference
Adjustment range: 1.0 … 20.0 K [2.0 … 40.0°Ra]
Factory setting: 6.0 K [12.0 °Ra]
S4 and S3 are used as the reference sensors for this function.
In system 8 the controller is equipped with an additional differential control for
heat exchange from a solid fuel boiler (e. g. pellet stove). The basic differential func-
tion is adjusted using the switch-on (DT3O) and switch-off (DT3F) temperature
differences.
When the temperature difference exceeds the adjusted switch-on temperature
difference, relay 2 switches on. When the temperature difference falls below the
adjusted switch-off temperature difference, relay 2 switches off.
DT3F
Switch-off temperature difference
Adjustment range: 0.5 … 19.5 K [1.0 … 39.0°Ra]
Factory setting: 4.0 K [8.0 °Ra]
Note
The switch-on temperature difference must be at least 0.5 K [1 °Ra] high-
er than the switch-off temperature difference.
Speed control
DT3S
Set temperature difference
Adjustment range: 1.5 … 30.0 K [3.0 … 60.0 °Ra]
Factory setting: 10.0 K [20.0 °Ra]
Note
For pump speed control of the heat exchange pump, the operating mode
of relay 2 must be set to Auto in the adjustment channel MAN2.
RIS3
Rise
Adjustment range: 1 … 20 K [2 … 40 °Ra]
Factory setting: 2 K [4 °Ra]
Note
The set temperature difference must be at least 0.5 K [1 °Ra] higher than
the switch-on temperature difference.
If the switch-on difference is reached, the pump switches on at full speed for 10 s.
Then, the speed is reduced to the minimum pump speed value (n2MN).
If the temperature difference reaches the adjusted set value (DT3S), the pump
speed increases by one step (10 %). Each time the difference increases by the adjust-
able rise value RIS3, the pump speed increases by 10 % until the maximum pump
speed of 100% is reached.
