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Heat recovery ventilation systems are an ingenious way of regulating the quality of the air in a building. They consist of two ventilation ducts- one passes air from the outside into the building, and the other does the complete opposite. At this point, many may worry about the constant change in air temperature this could cause, but those fears are allayed by the systems most vital component- the heat exchanger. This works by allowing the heat of the outgoing air (i.e. the air travelling out of the building) to transfer to the air coming into the building with the two air streams coming into contact by being absorbed through ducting in the heat exchanger's cavity. Typically, most systems are also hooked up to a fan system which allows the user to control the temperature and humidity within the building. An alternative to this system is called the energy recovery system, or ERV. It works in a similar way to the HRVC, but does not strip away the humidity from the outgoing air completely. This is so that the humidity remains consistent throughout the building, where it is needed.
Advantages and Disadvantages to the Heat Recovery Ventilation System
Advantages
The advantage of heat recovery ventilation systems is that they allow you to keep your building warm without having to use extra energy in the form of a central heating system or fuel burning system. This inevitably reduces fuel consumption and energy costs, which is a real bonus if you happen to be located in a colder climate, or it is winter. Similarly, during summer, a heat recovery ventilation system will reduce the demand for air conditioning since it allows the cool air flow directly into the building.
Another benefit to having a heat recovery system is that it keeps excessive moisture at bay, which is better for the building itself as it prevents damp, as well as your furniture, and ultimately your health.
Disadvantages
Although arguable the advantages outweigh the disadvantages, heat recovery ventilation systems are initially expensive to install and there is no way of accurately measuring their ability to pay for themselves. In addition, they are most suitable in climates where there tends to be a wide range of temperatures between winter and summer, e.g. Western Europe, as opposed to climates which have a more consistent range of temperatures, e.g. Subtropical Asia. As with all systems, HRVs also require periodic maintenance, as filters will require changing at least every six months or more.
