BA Systems—Petershvilevej 1—DK-3200 Helsinge—http://www.basystems.dk
23
BAS 918S/929S
Manual
Scheme 1, description:
Central heating control
Basic
The control topology for central heating is a mixing loop with outdoor temperature compensa-
tion of incoming flow temperature. Return limiter control is supported and may be enabled
when controlling scheme is selected.
Regulation
The incoming flow temperature is controlled by the motor valve. Regulation is from 0 – 100%.
The incoming flow temperature is then regulated in relation to the outdoor temperature, also
called climate compensation, defined as follows.
Outdoor temperature Forward temperature
Values in °C
At daytime, the circulation pump is stopped when the temperature exceeds 20°C. The pump
is reactivated if the temperature drops below 18°C. At nighttime, the circulation pump is
stopped above 18°C and reactivated below 16°C. Regulation stop is achieved by shutting of
the motor valve and stopping the circulation pump.
These are all default values that may be changed
Default activation:
The circulation pump is activated once every 24 hours if no other regulation is detected.
The valve for regulation is likewise activated once every 24 hours if no other regulation is de-
tected.
-20
75
-15
70
-10
67
-5
64
0
60
5
52
10
45
15
38
20
20
