The Importance of Flow Rates

Posted on December 2, 2022

In this video our HPIN training manager Jamie talks about flow rates and why it’s important.

Understanding the Impact of Flow Rates on Air Source Heat Pumps


One crucial factor often overlooked is the significance of flow rates. In this discussion, we’ll delve into the dynamics of flow rates and how they directly influence the efficiency and performance of air source heat pumps.

The Equation: Unveiling the Role of Flow Rates

Demonstrating the Impact

Let’s put this equation into action with a practical example. Suppose we’re using underfloor heating with a 30-liter-per-minute flow rate, a common scenario in many heating systems.

Adjusting the Flow Rate:

  • Lowering the flow rate by just 5 litres per minute results in a significant drop in heat output.
  • With a 25-liter-per-minute flow rate, the heat output decreases to 8.72 kilowatts.

The Significance of Adjusting Flow Rates

The comparison highlights how even minor adjustments in flow rates can lead to substantial differences in heat output. This underscores the critical role that flow rates play in the efficiency and effectiveness of air source heat pumps, especially in scenarios with lower delta T values.

Glycol and Its Impact

Adding glycol to the system further complicates matters. Glycol, while sometimes used for antifreeze purposes, diminishes the heat output even more. Understanding these dynamics is essential for optimizing the performance of air source heat pumps.

In conclusion, flow rates are not to be underestimated in the realm of air source heat pumps. They are key determinants of efficiency and can significantly impact the overall performance of heating systems. By grasping the intricacies of flow rates, we can enhance the effectiveness of air source heat pump installations and ensure optimal heating solutions for diverse environments.