Maximum calorific value use with high hot water output doesn’t have to be a contradiction in terms

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Apartment buildings, hotels and sports facilities often need hot water in great quantities during peak times so that everyone can shower at the same time. What is the most efficient, environmentally friendly and space-conserving way of providing this hot water?

It’s a familiar problem: conventional hot water provision systems such as register tanks often do not provide enough output to accommodate sudden jumps in hot water demand. Moreover, tanks with large dimensions take up an awful lot of space, suffer from high standby losses and reduce the efficiency of the overall system due to the high return temperatures. 

What’s the solution to this?

A system designed for low return temperatures and featuring a hot water tank and a large heat exchanger surface for high hot water outputs is needed. A tank charging station with a heat exchanger offers a great alternative: the heat exchanger transfers more energy and lowers the return temperature. The lower the return temperature, the greater the condensation and therefore efficiency. Another advantage is that this system works with a significantly lower storage volume. This provides efficiency, saves space and conserves energy. 

Hydraulic scheme UltraGas, TransTherm_aqua_LS

Perfect trio: condensing boiler + TransTherm aqua LS + hot water tank

And that’s where the system solution comes in: 

  • UltraGas®
  • TransTherm aqua LS plus 
  • hot water tank

The solution allows you to benefit from the advantages offered by the UltraGas® gas condensing boiler with its robust, stainless-steel heat exchanger and the separated high/low-temperature returns, which ensure an optimum level of efficiency. The low return temperatures of around 30°C are achieved by means of the TransTherm aqua LS tank charging station with the integrated second heat exchanger. 

Diagram with temperatures: UltraGas, TransTherm aqua LS and tank

The smart thing about this solution is that the second heat exchanger takes on the task of return cooling to ensure a constant return temperature, thereby boosting the condensation effect of the UltraGas®. Each improvement in condensation means an increase in efficiency whilst simultaneously reducing CO2 emissions. And to top it all off, the system solution boasts modest space requirements and excellent flexibility while requiring just one controller – the TopTronic® E.

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Günther Köb

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