12Application 11 - Danfoss ECL 2000 Installation Manual

Application 11
6.3.12 Application 11
System diagram 11A
Heat circuit 1
Heat circuit 2
Hot-water circuit
84
Two separate heat circuits with common primary heat exchanger for a heat circuit
and a hot-water circuit with indirect control.
The motor valve M1 controls the flow temperature, which is measured by the sen-
sor S1. The return temperature measured by the sensor S2 can be limited. The cir-
culation pump P1 is running when the reference flow temperature is above 20 °C
or the outdoor temperature is below 2 °C.
The motor valve M2 controls the flow temperature, which is measured by the sen-
sor S4. The return temperature measured by the sensor S5 can be limited. The cir-
culation pump P2 is running when the reference flow temperature is above 20 °C
or when the outdoor temperature is below 2 °C.
The hot-water circuit is connected to the secondary side of the heat exchanger, in
parallel with heat circuit 2. The charging pump P3 performs on/off control of the
storage tank temperature, which is measured by the sensor S6. Service-water
heating takes priority over room heating, i.e. the circulation pump P2 in heat cir-
cuit 2 is stopped during tank charging. The pump P4 maintains circulation through
the storage tank but is not controlled by the ECL 2000.
EI.65.D4.02