Figure 98:
Heat exchanger connection
The heat exchanger operates according to the cross-counter-flow principle. Only preheat can be
supplied for parallel flow operation on request.
1. All standard heating and cooling heat exchangers - counter flow
2. Steam heat exchangers: steam inlet top, condensate bottom - counter flow
3. Preheat heat exchanger (freezing risk - on request) - parallel flow
Hydraulic connection schemes of heating or cooling coil should be carried out as shown in the
scheme
with a three way valve as a mixing valve. Compared with a flow control using a
straight-through valve this connection avoids unequal temperature profiles, in that way air heating
or cooling is quite uniform along the coil surface.
Figure 99:
Hydraulic connection scheme
To vent and drain the heat exchanger connection, valves are mounted (on request). To ensure
correct operation must be ensured, however, that the vent is on the highest point of the whole wa-
ter cycle and the drain at the lowest. Otherwise, the valves shall be mounted on another suitable
point in the circuit.
Figure 100:
Drain valve
Figure 101:
Vent valve
6.1.2 Steam heat exchanger
The heater is heated to above 70 °C, next to heater plastic parts are installed. To prevent damage
on the plastic parts, on responsibility of the client is requested the following:
