what is the difference between a variable frequency heat pump and a fixed frequency heat pump?


release time:

2023-08-08

Variable frequency heat pumps (also known as inverter heat pumps) and fixed frequency heat pumps (also known as on/off heat pumps) are both types of heat pump systems used for heating and cooling. They differ primarily in their control mechanisms and how they modulate their output to meet comfort needs while optimizing energy consumption.

Variable frequency heat pumps (also known as inverter heat pumps) and fixed frequency heat pumps (also known as on/off heat pumps) are both types of heat pump systems used for heating and cooling. They differ primarily in their control mechanisms and how they modulate their output to meet comfort needs while optimizing energy consumption. Here's a comparison of the two from the aspects of comfort and energy saving:

Variable Frequency Heat Pump:

Comfort: Variable frequency heat pumps offer a more consistent and precise temperature control. They adjust their compressor and fan speeds to match the heating or cooling demand of the space, maintaining a more stable indoor temperature without large fluctuations.

Energy Saving: Variable frequency heat pumps are more energy-efficient than fixed frequency ones. They can modulate their output to match the actual load, which means they don't need to cycle on and off as frequently as fixed frequency heat pumps. This leads to reduced energy consumption and more efficient operation.

Noise Level: Variable frequency heat pumps tend to operate at lower fan and compressor speeds, resulting in quieter operation compared to fixed frequency units that may turn on and off abruptly.

Longevity: The gradual startup and shutdown of variable frequency heat pumps put less stress on components, potentially leading to a longer lifespan compared to the frequent on/off cycling of fixed frequency units.

Fixed Frequency Heat Pump:

Comfort: Fixed frequency heat pumps may have temperature fluctuations due to their on/off cycling nature. When they reach the desired temperature, they turn off until the temperature falls below a certain point, leading to potential temperature swings.

Energy Saving: While fixed frequency heat pumps are less energy-efficient than variable frequency ones, their upfront costs tend to be lower. However, this efficiency difference could lead to higher energy bills in the long run.

Noise Level: Fixed frequency heat pumps can be noisier, especially during their startup when the compressor and fan kick in.

Longevity: Frequent on/off cycling might result in more wear and tear on the components of fixed frequency heat pumps, potentially impacting their overall lifespan.

In summary, variable frequency heat pumps provide better comfort through consistent temperature control, are more energy-efficient due to their ability to modulate output, and tend to operate more quietly. Fixed frequency heat pumps might have a lower upfront cost but could lead to higher energy consumption and potentially offer less precise temperature control and shorter lifespans due to their frequent cycling.