Diagram 48
14
Program 49:
If the tank has reached its maximum temperature due to the solar power sys-
tem, solar pump
A1
and feed pump
A2
are switched on (
reverse cooling function
).
A2 ... or
T4 > max1 & T5 < T4
All Pr2:
Output
A4
(burner requirement) switches on when
T2
falls below threshold
max4
and switches off when
T3
exceeds
max3
.
Max3
is no longer the tank limit for the
oil/gas boiler feed pump.
A1 = T1 > (T4 + diff1) & T4 < max1
A2 = T5 > (T4 + diff2) & T5 > min1 & T4 < max2
A3 = T6 > (T3 + diff3) & T6 > min2
A4 (on) = T2 < max4 – hysteresis
A4 (off) = T3 > max3
All Pr4:
Three independent differential loops. The tank feeding
A2
from the solid
fuel boiler is controlled by the difference
diff2
between boiler sensor
T5
and the sensor
T2
(tank top)
A1 = T1 > (T4 + diff1) & T4 < max1
A2 = T5 > (T2 + diff2) & T5 > min1 & T2 < max2
A3 = T6 > (T3 + diff3) & T6 > min2 & T3 < max3
A4 (on) = T2 < max4 – hysteresis
A4 (off) = T2 > max4
T1 T5 T6
min1 min2
diff1
A1 diff2 diff3
A2 A3
T4 T3
max1
max2
Required settings:
diff1
…coll. T1 – TK T4
A1
diff2
…sf-boiler T5 – TK T4
A2
diff3
…oil boiler T6 – TK T3
A3
min1
…switch-on temp. sfb T5
A2
min2
…switch-on temp. ogb T6
A3
max1
…limit TK T4
A1
max2
…limit TK T4
A2
max3
…burner requ. OFF TK T3
A4
max4
…burner requ. ON TK T2
A4
Burner A4
T2 max4
T3 max3
T1 T5 T6
min1 min2
diff1 diff2 diff3
A1 A2 A3
T4 T2 T3
max1 max2 max3
Required settings:
diff1
…coll. T1 – TK T4
A1
diff2
…sf-boiler T5 – TK T2
A2
diff3
…oil boiler T6 – TK T3
A3
min1
…switch-on temp. sfb T5
A2
min2
…switch-on temp. ogb T6
A3
max1
…limit TK T4
A1
max2
…limit TK T2
A2
max3
…limit TK T3
A3
max4
…burner requirement TK T2
A4
Burner A4
T2 max4