ST – 480
the controller based on the outside temperature. In our controller this curve is
established based on four temperature set-points selected for their respective
outside temperatures. Set-point temperatures must be provided for the
following outside temperatures: -20ºC, -10ºC, 0ºC and 10ºC.
The more points there are available for constructing the curve, the greater
is its accuracy, which allows you to determine its shape in a flexible way. In our
case, four points seem to be a very good compromise between accuracy and
ease of setting its shape.
Where in our controller:
X
A
= -20ºC,
X
C
= 0ºC,
X
B
= -10ºC,
X
D
= 10ºC,
Y
A
, Y
B
, Y
C
, Y
D
– set-point valve temperatures for their corresponding outside
temperatures: X
A
, X
B
, X
C
, X
D
After
weather control
is enabled the
valve set-point
parameter is
calculated based on the heating curve. By changing this parameter you can
decrease or increase all the weather control settings.
III.a.9) Return protection
This feature allows you to enable protection for the boiler from excessively cold
water returning from the main circuit, which could cause the boiler to suffer
from low-temperature corrosion. The return protection function works to ensure
that when the temperature is too low the valve will close partially until the short
circuit of the boiler reaches the desired temperature. This feature also protects
the boiler from a dangerously high return temperature to prevent water from
boiling.
When this function is enabled you need to set the minimum and maximum
return temperatures.
III.a.10) Room thermostat reduction
This function is active only when the unit is operated with a (standard or
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