33
-
There is no “OpenTherm
®
” thermostat connected (to terminals 5 and 6 of X4).
-
There is heat demand from simple time clock or room thermostat (terminals 2 and
3 of connector X4).
-
Parameter u (Base point according to Recom) is set between 1 - 60°C (factory
setting = 20°C).
Note:
The
outdoor sensor (max. cable length 50 m) should be located on a north fac-
ing wall out of direct sunlight.
Parameter u
(Base point) can be found in the user menu of Recom,
see Par. 9.3.
During a heat demand (HTG), the boiler contol unit will follow a heat slope. The out-
side temperature (
è
), the (HTG) Flow temperature setpoint (
é
) and parameter 52
(Recom) are used as input parameters for calculating the angle of the heating slope.
Weather compensation slope setting:
- Outside temperature min. set point = 0°C (parameter 52, variable between 1 and -15°C)
- Outside temperature max. set point = 20°C
- Flow temperature set point at max. outside temperature = 20°C (parameter u,
variable between 1 and 60°C)
- Flow temperature set point at min. outside temperature = 80°C (parameter 1,
variable between 20 and 90°C)
This means that at 0°C outside temperature the boiler will go to a flow temperature
of 80
o
C, at 20
o
C outside temperature the boiler will go to a flow temperature of 20
o
C
(parameter u),
see Fig. 20.
80
0
Fig. 20
Weather compensation slope
ë
=
variable
é
=
flow temperature setpoint
è
=
outside temperature
