The whole truth about heat pumps - which one is the best?

By: Raigo Vihalem

This question is probably in the mind of everyone involved when it comes to choosing a heat pump as a source of heating for your home. In order to get to the bottom of it, we have to start from the beginning. What is a heat pump and how does it work? Generally, the operation principle of the heat pump is the same for different systems. Should I choose air-to-air, air-water or geothermal heat pumps?

In short, it is obtaining the heat with the help of the external environment, for the heat pump operation cycle, regardless of whether it is an air-to-air, air-water or geothermal heat pump.

Typically, standard solutions, or split systems, have one external device and one internal part, between which the state of the gas changes with the help of the compressor. This means that gas changes from gaseous to liquid and vice versa. The external part of the heat pump includes a compressor and an internal heat exchanger to separate the water and gas. The water is inside the house, e.g., for radiators or underfloor heating. Combining the internal and external parts of the split systems requires professional skills, and a layperson cannot do it. The devices are connected to each other by a copper pipe and the heat pump gas, i.e., freon circulates in it. The danger of leakage of freon from pipelines and equipment is extremely high. That is why all piping connections and welds must be done carefully and correctly. Nonetheless, from time to time, freon may start to leak out of the connection places as they are locally fitted, and uncomfortable installation may also result in installers making mistakes. This risk is undoubtedly present and not small. Even finding very small leaks can prove to be extremely complicated. The availability of skilled labor has become relatively impossible today, as there are many heat pump suppliers, but there is a shortage of skilled labor.

Keep in mind the efficiency!

An important nuance that should be taken into account when choosing the heat pumps is the efficiency. What the vendors generally declare in the technical documentation as the heat pump's efficiency does not actually take into account the length of the pipeline and is only the efficiency of the compressor. What difference does it make? This makes a lot of difference as the efficiency decreases as the length of the pipeline increases, and it is usually not indicated as a negative factor. Thus, the more complicated the installation, the greater the work must be done by the heart of the heat pump - the compressor. If a person had, for example, 1.5 times more blood vessels, then the work of our heart would be very difficult.

What would be an alternative to standard solutions and what would minimize the risks mentioned above? One good alternative would be an air-water heat pump with a gas or freon component already installed in the factory, and the water is already emitted to the house from the heat pump, so that is the so-called water system. Such a system is also called a monoploc device that does not have an internal part. The efficiency of the water system is independent of the size of the system.

How has the number of supporters of such systems distributed by regions?

• Japan and Korea: great support for split systems
• Europe and USA: extensive transition to water systems

Why should water systems be preferred to split systems? Especially for the environment. In the coming years, the effect of freon on the external environment will be significantly reduced. And that's why the amount of freon in the systems must be reduced. This is especially true so that the next generation could also enjoy what we have built and the planet could remain green.

Split systems coming from Japan and Korea do not have certificates and test reports that are important to assess the correctness of the parameters issued by the factory. There is only data provided by the factory. On the contrary, water systems have independent laboratory certificates, such as EUROVENT and AHRI. The water systems are welded by certified personnel, and all leakage points are carefully tested. There is no certificate for welding and joining split systems.

Based on this information, it can be concluded that the best heat pump solutions are those that are not yet widely used in Estonia, but which have the future - water systems!

If you feel that you are interested in the topic, see: www.aermeceesti.ee