Ask any health expert, HVAC technician, engineer, or contractor, and they’ll tell you that ventilation is critical in a home. Ventilation is the ‘V’ part of your HVAC system and is absolutely necessary for maintaining healthy airflow, clean breathable oxygen, and the best overall indoor air quality (IAQ) for your home. There are numerous types of ventilation systems – with varying degrees of efficiency and quality – but on a whole, they are all made to bring fresh air in and push stale air out. Here’s a little breakdown of the types to help you decide how to optimize the air flow in your home.
According to our resident heating and cooling expert Keith Hill, the manager of technical support at Minnesota Air, the simplest and least expensive type of ventilation is natural infiltration. However, it’s also the most unreliable.
“This is a process in every home where the wind blows, causing air to leak in by way of the cracks and crevices in the doors and windows,” he says. “It is a form of natural ventilation. The stronger the wind the more ventilation you get.”
There are homes that are built with natural ventilation as part of the design, but many of those houses are located in tropical climates that can be opened to the elements year round.
“If fresh air is important to keep us healthy, why would we rely on gusts of wind to provide it?” says Keith.
Basic Powered Systems
The next step up from natural ventilation is a basic powered system. Keith says the simplest powered system uses an electric exhaust fan or blower to pull air from the home. That puts the home in a slight negative pressure that will make air get pulled through the cracks and crevices, into the outdoors.
Unfortunately, this system can come with problems too, he says, because it may give you trouble with natural drafting chimneys and vents. For example, a down drafting chimney – one where the pressure pulls the outside air back in the home down the chimney – can be dangerous because if you have a fire going, the combustibles and gasses like carbon monoxide can re-enter the home instead of getting pushed out.
“Any form of infiltration, natural or forced, has a basic flaw – a big one,” says Keith. “It takes your conditioned air – air that you’ve already paid good money to heat or cool – and sends it outside and replaces it with fresh unconditioned air that needs to be heated or cooled.”
And if you are looking to save money, getting a more efficient system is cost effective and beneficial to your health.
Balanced Systems & HRVs
Finally, the best ventilation system you can get has a balance – equal exhaust with fresh air. And that means there will be no negative pressure in the home. In addition, it will also be able to transfer heat energy from the old air leaving your home into the incoming air. This system is called a heat-recovery ventilator (HRV), and it is one of the two types of energy-recovery ventilation systems. The other is the simply named energy-recovery ventilator (ERV). According to the Department of Energy, both systems provide the best air quality and energy efficiency, but differences in the way the heat exchangers work determine the right type to use depending on the climate.
“Heat Recovery Ventilators (HRVs) are 65 to 75 percent efficient in the transfer of heat energy, and they are easily balanced so that both incoming air and outgoing air is precisely the same,” Keith says. “They also have filters so the incoming air is cleaned before it enters the home.”
Plus, there are controls that allow very, very low continuous ventilation, he says, and with a flip of a switch you can boost your ventilation rate to get rid of any odors or fumes like cleaning products, cat box smells, or even any evidence that you burnt the popcorn.
If you are interested in learning how an HRV can be integrated into your HVAC system, give the team at StayComfyMinnesota.com a call and we’ll show you the difference.