Engineered Systems » Water » Water–water
Hot water compact station
baelz 143 Moduline
The decrease in the water temperature of the primary flow line by adding the return flow with the jet pump reduces the temperature spread and thus increases the quantity of water passed over the heating surface.
The admixture control using the jet pump on the primary side of the heat exchanger is the decisive improvement compared to the throttle circuit.
This difference results in the following advantages for the entire system:
• Good controllability across the whole output range.
• Reduction of the strain-induced tension.
• Reduction of liming on the secondary side.
• Reduction of the differential pressure variations on the primary connections of the heat exchanger.
Short - an extension of service life
Most heat exchangers (tubular heat exchangers and plate heat exchangers) are still controlled by a throughway valve in throttle circuit. This throughway valve is used to control the mass flow (energy) in dependence on the power demand of the consumer connected to the heat exchanger (Fig. 1).
In this setup the primary flow temperature is always equal to the temperature entering the heat exchanger. This inlet temperature is not dependent on the load, but is defined by the operator of the primary network. This means that in partial load operation of the consumer, the inlet temperature on the primary side of the heat exchanger is unnecessarily high.
This results in a big temperature difference between the inlet on the primary and on the secondary side. This temperature difference produces thermal tensions in the heat exchanger. Tensions are a frequent cause for damage, in particular in plate heat exchangers. Moreover, a big temperature difference causes a low quantity of water. This in turn results in bad heat exchange due to transition to laminar flow. Complicated conditions are produced for control.
The use of a jet pump instead of the control valve permits admixture without any additional costs worth mentioning. Fig. 2 illustrates the admixture system with a jet pump with all its advantages.
Additional Engineered Systems for water
The economic type of water heating
baelz 143 Moduline
Baelz-Moduline can be integrated in all modern energy supply systems: solar systems, wood boiler, heat pump, combined heat and power
stations, et cetera.
Baelz-Moduline stands out for its compact construction. The installation is very easy as the modules are mounted on a steel frame and are wired ready for connection.
