Heating and Cooling System
The heating and cooling of the house or “comfortable living” is the main source of energy consumption in the building. Energy is used to ensure a favourable climate in the living areas. By improving thermal retention, specific heat losses are also reduced. Small heat losses require low-temperature heating systems and the use of renewable sources. For these reasons, most prefabricated houses are heated by radiant heating (underfloor). This heating system, due to low heat demand, operates at low temperatures, which ensures that the floor never feel excessively warm; therefore, the underfloor heating never negatively affects the user. In a very good passive house, we can ensure a comfortable living environment with only the help of hot-air heating, provided by the ventilation system, for most days of the year. For longer cold and foggy periods, when there are no solar heat gains and external temperatures are persistently below zero for a long time, investors most commonly decide to install a fireplace in order to maintain the desired temperature.
At Rihtar, we install compact devices that combine all the necessary components for heating/cooling, ventilation and heating of domestic hot water as a standard element. It operates according to the principle of interconnection between these components and thus achieves maximum efficiency. This concept is designed differently to other heating systems. The compact device with the air-air heat pump system collects heat from the waste air and heats the intake air for ventilation (reverse system for cooling during summer). In this process, the two-stage utilisation of waste air energy also provides hot domestic water.
To Heat or Not to Heat a Passive House?
A nearly zero-energy house almost does not need heating as most of the heat needed is acquired through indirect (passive) means. However, heating is still required due to the very high comfort of living criterion and the unpleasant outside climate. At Rihter, we advise you when choosing a suitable system and make sure that we do not increase construction costs unnecessarily.
There are two heating systems:
- alternative heating sources and
- compact devices for heating.
One of the most important factors for ensuring well-being is fresh and pleasant air, which has a significant effect on our health and well-being in a room. A ventilation system with heat recovery is a must in modern, airtight buildings, and is installed in all our buildings as a standard element. The ventilation system provides a constant inflow of fresh air into the building. Fresh outdoor air from the outside of the building is drawn through the ventilation louvre and supplied to ventilation devices. It then flows through the distribution systems into the living areas (living room, dining room, bedroom, children’s room, work room). Waste air (exhaust) is drawn from rooms saturated with moisture and smells (kitchen, toilet, bathroom, and utility rooms) and is then extracted via an outlet system to the ventilation device and then into the surrounding area. It must be emphasised that the air inlet and outlet are not mixed, but only exchange energy (heat). This ensures constant fresh air with minimal energy losses. Modern ventilation systems enable heating of the building during winter and cooling during summer.
Alternative Heating Sources
Heating of domestic hot water with solar collectors.
The alternative heating sources enthusiasts can choose to heat their house with solar energy from collectors in combination with a fireplace and a water heat exchanger. In this case, it will occasionally be necessary to light the fireplace during winter, when there is not enough sun and severe cold persists.
Modern solar systems, when properly dimensioned, cover over 90% of the annual consumed energy for the preparation of domestic hot water and heating. Generated solar power can also support heating via different heat exchangers; plate heat exchangers are recommended. This means that more collectors with a larger hot water supply are needed, where the heat can be stored for a day or two.
This system works very well if the house is located on an ideally orientated higher location, where there is a lot of sunshine even during winter. We must not forget that the biggest obstacle to heating with solar energy is fog during winter, when we need the most energy for heating. Generating solar energy during a longer period of bad and cloudy weather can also prove rather challenging. In case of said heating, more expertise and experience are needed for the design and implementation of such a system, as well as more knowledge regarding the use of installed devices if you want to achieve good efficiency. Due to the complexity of this system, we recommend it only to experts.
At Rihter, we have taken a step forward in the field of heating, ventilation, and domestic hot water heating. For many years, we have been installing compact devices designed by the Danish manufacturer, Nilan. A compact device is a device that combines all the necessary components for heating/cooling, ventilation, and domestic hot water heating. All these components ensure the best use of energy. It operates according to the principle of interconnection between all these components and thus achieving maximum efficiency. An important advantage of compact devices is that the heat and waste heat from ventilation is used for heating domestic hot water. The device is small and does not take much space, therefore it is suitable for installation in a bathroom, a smaller utility room or a storage room.