Beating the low Delta T syndrome in one-pipe heating applications

Reduce heat loss and increase system efficiency

Your challenge:

In a one-pipe heating application, hot water typically enters the system at the top of the building and is distributed down through the pipe, heating up radiators one after the other. However, if one radiator is closed, the water is by-passed between the flow and return pipe leading to increased return temperatures and a lower Delta T. This results in increased return water temperature and substantial fines from the heating plant to the building's owner.

Our solution:

Changing the main pump in the system to a Delta T controlled Grundfos TPE pump is the first step. However, there is still no guarantee that a building's inhabitants who are furthest away from the pump will actually receive the heat they require. Grundfos therefore includes a sensor on the system's critical spot to monitor and control the Delta P – the difference between pressure (deliver) and suction (income). This combined solution secures optimum operation in terms of economy, and at the same time delivers the right comfort for occupants. 

Discover how the tenants of a seven-storey building in Langenæs, Denmark reduced their heating bills with the Grundfos TPE3's integrated Delta T control. Read more about this innovative solution to significantly reduce energy consumption.

Delta T control with the TPE3

See how the TPE3 with integrated Delta T control takes charge of a system's need for flow, ensuring increased efficiency and lower energy consumption. 

The intelligent solution: multiple control modes

By utilising sensors and multiple control modes in one Grundfos pump solution, you can ensure your system never underperforms. The TPE3 measures and compares the temperature of both the flow and return pipes. At the same time, differential pressure is measured at the system’s critical spot, which is furthest away. This way you not only secure optimal economy by measuring Delta T, but you also secure occupant comfort by measuring Delta P. Together, this ensures you have complete control of Delta T.


Explore the many benefits of the Grundfos TPE3:

  • Delta T control mode as standard
  • MGE motors with IE5 status - the world's highest energy efficiency rating
  • Flowlimit
  • Built-in heat energy meter
  • Integrated wireless multi-pump control
  • Limitless connection to external sensors

Grundfos is proud to introduce its MGE pump motors with the new IE5 status - the world's highest energy efficiency rating. Discover how our ground-breaking Grundfos iSOLUTIONS motors meet the strictest IE5 criteria to deliver you an unsurpassed level of energy efficiency.

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