3.2. Mounting and Electrical Connection
Mounting
• First, fix the back plate of the RAMSES 850 top using the
enclosed fixings. Use the back plate as drilling pattern.
• Avoid fixing the room thermostat to an exterior wall, see note
6.5.4.
The ideal place is an interior wall at about 1.5 m height.
• Do not install near radiators, windows, televisions or
heat dissipating devices.
The room thermostat measures the temperature of the room in
which it is placed and regulates it according to the programmed spe-
cifications. Therefore, avoid an unintentional interference with the
measurement of temperature; errors could occur in the temperature
control.
Weather Compensation Control
You can connect an external temperature sensor to the terminal
with the designation “DIGI”. The room thermostat automatically
recognizes the sensor and regulates the temperature measured by
the remote sensor.
Electrical Connection
The heating boiler with OpenTherm connection provides
the thermostat with power. For that purpose the boiler is
equipped with a safety transformer.
The two-wire low voltage connection (OpenTherm) is not polari-
zed, i.e. the wires can be connected as desired to the terminals of
the heating boiler.
Do not lay the thermostat cable in the same cable channel as the
230 V mains cable.
Do not lay it parallel to a power cable.
Before connecting the thermostat, disconnect the heating boiler
from mains by unplugging the mains cable.
Attention
The thermostat must not be connected directly to a 24 V
connection or to the terminal for an ON/OFF-thermostat.
This could cause irreparable damage to the thermostat.
Make sure that the thermostat is connected to the right terminals
before you connect the heating boiler again to the power supply.
Interferences and changes to the thermostat will lead to the loss
of warranty claims.
Note
Only connect this thermostat to a boiler with the OpenTherm
Logo .
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