Filenews 22 April 2022 - by Vassos Vassiliou
Winter may have passed and with it the need to heat homes, apartments, offices and generally workplaces and entertainment venues, but in the months that follow, until October, heating costs will succeed the cost of cooling.
The skyrocketing cost of fuel and, by extension, the filling of oil and LPG tanks, lead citizens to seek the cheapest solution of maintaining a bearable temperature in the places where they live or operate.
The Second Vice-President of ETEK and Mechanical Engineer, Eliza Vassiliou, explains to "F" that it is appropriate to act in order not to waste money or even to reduce the cost to the existing systems we have in our homes/ apartments.
For the summer, maintenance of air conditioners is recommended, which if they are of old technology, and by extension energy-intensive, it is advantageous to replace them, while for the winter the heat pumps are judged by Mrs. Vassiliou as the most advantageous for heating, since their use is 35%-40% cheaper. Oil is expensive and LPG is expensive but it is cheaper than oil. Heaters are a cheaper solution (without meaning that they do not burn) but in practice, they simply heat the air and a relatively small space, leaving the walls and floors cold.
For the summer months, Mrs. Vassiliou mentions that modern air conditioners are the best solution that creates comfortable living conditions. However, if you buy a new air conditioner, you suggest that the criterion should not be the purchase price but the efficiency and the economical operation and of course the life time of the air conditioner. However, if an air conditioner is, for example, 15 years old, then it is worth replacing it which, as she says, will bring savings that will cover the purchase price.
Furthermore, as far as air conditioners are concerned, it submits the following suggestions:
1. Cool the house when the temperature is low, i.e. early in the morning or late in the afternoon.
2. If you have sunshades (shutters, awnings, curtains) we have them closed during the hours with high solar radiation and we open them the rest of the hours.
3. The thermostat of the air conditioner should be adjusted to 25-28 degrees in order not to have a large temperature difference from the external environment. The greater this difference, the greater the heat losses to the environment. In addition, extreme temperatures cause dryness of the air in the room that creates discomfort.
4. We turn off our device completely when no one is in the area.
5. We adjust the blinds of the air conditioner so that the air is directed high to achieve proper distribution of air in the space. The speed of the air flow should be such that it does not create strong currents in space (low).
6. The air of the premises should be regularly renewed (air conditioners recycle the air of the room, do not put fresh air in the room).
7. Air filters should be cleaned at least once a month (simple washing by users). If they are not cleaned, air circulation is slowed down and the efficiency of the air conditioner is reduced. In addition to these, an unhealthy environment (powders and pollutants) is created, causing breathing problems and allergies.
8. Once a year the air conditioning units must be maintained by qualified personnel. An air conditioner that is not properly maintained, shows reduced efficiency by about 5%.
9. We replace the old air conditioners with new, changing frequency (Inverter) and high energy efficiency. In this way, great energy savings are made and they are quieter.
Heat pumps for the winter
Regarding the heating of the premises during the winter months, Mrs. Vassiliou believes that the best option is the heat pumps, which operate with electricity and their great advantage is that they consume about 35%-40% less electricity compared to other heating methods. She also explains that if they are combined with the installation of photovoltaic systems, the result will be even better for the owners.
She also observes that the efficiency of the boiler which runs either with oil or LPG is lower.
Regarding the installation cost of the heating pump system compared to LPG or diesel boilers, it is higher than €3,000-€4,000, but decreased compared to the initial stage of purchase and installation. The difference in installation costs depends on several factors, such as in-house orientation, height and insulation.
But in an existing house with a conventional boiler (oil / LPG) we cannot simply remove it and install another one. Heat pumps operate at lower temperatures so if we are talking about underfloor heating the pipes must be installed differently, while the bodies will also be different, so essentially the whole system has to be ripped off which has a cost.
For an average home (in terms of area) the installation of a heating pump ranges from €10,000-€12,000 while other heating methods (LPG and oil) cost about €2,000-€3,000 less.
Regarding the installation and the fears expressed, Mrs. Vassiliou indicates that when the installation is done by an authorized person, it is safe. There are, she added, many safeguards.
She also explains that with central heating (oil / LPG) the structural elements of the building (walls and floors) are heated, which emit back the heating, so the house remains for some time warm even when we turn off the heating, which is not the case with the various heaters.
