Inverter Heat Pump VS Heat Pump
We provide two types of heat pumps: standard and inverter heat pumps. We have more than ten years of valuable experience in the manufacture, installation and maintenance of heat pumps, so we decided it is time to increase the inverter series because it has many advantages in house heating.
What makes inverter heat pumps the preferred heat pump? In this article,
we will explain in detail the difference between an inverter and a standard
(also called on/off or fixed output) ordinary pump.
What is the difference between these two technologies?
The energy required to maintain a specific temperature varies greatly
with the surrounding environment temperature and the required temperature.
The fixed output heat pump can only be turned on or off. When it is
turned on, the constant output heat pump works at 100% capacity to meet the
needs of household heating. It will continue to do this until it reaches the
desired temperature, and then it will cycle between closing and opening to try
to maintain that temperature.
However, inverter heat pumps use variable speed compressors to adjust
their output, increasing or decreasing their output power to match the exact
heat requirements of the house.
When the demand is low, the heat pump will reduce its output, limit the
power consumption and the load imposed on the heat pump components, and limit
the start-up period.
Starting current
Inside the standard heat pump is a compressor driven by an AC motor. The
starting current of any AC motor is usually seven times higher than the normal
operating current. This means that it needs more power to start turning than
when it is at running speed.
The inverter heat pump uses a DC motor, which can rise slowly and avoid
high starting current. This has many advantages:
1. It uses less power to start-saving you money.
2. It reduces the thickness of the cable required for installation. This
can significantly save installation costs.
3. It eliminates annoying tripping, which is sometimes a problem with
larger single-phase power supply units.
4. It reduces the start-up "pressure" of the machine.
5. It makes it possible to run a heat pump from an off-grid solar power
system of the correct size.
Noise
Inverter heat pumps can run more quietly than standard heat pumps. In
the 100% output power mode, the inverter pump is already quieter than a
standard heat pump of the same size. When the inverter unit is running in the
"quiet" mode, it is equivalent to inserting earplugs when using a
standard heat pump.
Efficient
Compared with traditional fossil fuel combustion heating systems, both
fixed output and inverter heat pumps provide a higher level of energy
efficiency. A well-designed standard heat pump system will provide an average
coefficient of performance (COP) of approximately 5. This means that for every
1 kilowatt of electrical energy used to power the heat pump, it will return 5
kilowatts of heat energy. Use the inverter heat pump to obtain a COP value of
more than 12! Some marketing materials show values much higher than this
value, but it is important to know that the COP value depends on the
environment and water temperature, and it is misleading to test it under
unrealistic conditions to show a higher COP value.
It is also important to know that when running at 100% output capacity,
the inverter heat pump will provide you with more or less the same COP value as
a standard heat pump. Only when the inverter heat pump "back off",
its output power will begin to improve efficiency.
Let us assume that the customer wants their indoor temperature to be kept at 20°C at all times-even in the worst case, the ambient temperature in winter is 0°C. We also assume that for a house of a certain size, when operating at 100% output capacity, a 16kW inverter heat pump will be able to meet this requirement. When the ambient temperature is 0°C (operating at 100% output capacity), the inverter heat pump will not provide greater power savings than the standard heat pump. However, when the ambient temperature rises and the heat pump does not need to operate at 100% output capacity, the inverter heat pump will become more efficient and can provide significant power saving advantages. At an ambient temperature of 18°C, the output power of the inverter heat pump may have been reduced to 30%, and the power used is less than half of the standard heat pump.