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Q. What purpose do Heat Recovery Ventilators serve?
A. They provide an energy efficient way to bring in fresh filtered air while removing stale air.
A heat recovery ventilator (HRV) brings in fresh air from the outside, preheats the incoming air during the winter and precools the incoming air during the summer. It can provide clean fresh air every day while helping to keep energy costs low.
The American Lung Association recommends HRVs and sealing of air leaks to protect your health while conserving energy.
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| A. The heart of an air-to-air HRV system is the heat recovery ventilation unit which houses the heat exchange core. |
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The HRV unit can connect to existing
ductwork.
1. One set of ducts collects
stale moist air from the kitchen, laundry and bathrooms. This stale
contaminated air passes through the HRV unit and is exhausted to the
outside.
2. The other ducting system draws in fresh clean air from outdoors through the HRV unit.
3. As the two air streams pass each other within the heat exchanger core, heat is transferred from the outgoing stale air to the fresh incoming air. There is no mixing of air streams.
4. The HRV unit is able to capture up to 85% of the energy from the outgoing stale air. Filtered, preconditioned fresh air is delivered where you need it - in the living areas of your home.
A.
Tight
buildings reduce energy costs by keeping in the heated or air
conditioned air. But tight buildings without adequate ventilation trap
humidity and pollutants so they feel "stuffy", aggravate allergies and
cause general discomfort for you and your family. Moisture damage to
windows and other parts of the building shell can result when humidity
is too high.
A. An open window doesn't filter the incoming air or accurately control ventilation rates. An HRV is designed to be energy efficient and exchange the air to:
An open
window can't do all these things for you.
A. Maybe, but do you ever notice a build up of moisture on your windows and window sills? If you do, an HRV is recommended to exhaust excessively humid air. In today's tightly built homes moisture can build up. Each average person puts about 6 pounds of water into their home each day while breathing, cooking, and cleaning. Excessive moisture build-up on windows and sills shows that your current system isn't working well enough.
Do you want to provide just the amount of ventilation you need for comfort and safety while avoiding expensive and uncomfortably excessive ventilation. You can achieve these goals by following two steps recommended by The American Lung Association recommendations:
A. It can be a problem both for you and for your home.
Excess moisture can contribute to health
problems associated with
mold allergies,
and microorganisms. Excess moisture can seep into the walls and
woodwork, causing dry rot and other structural problems. Other bad
effects of excess humidity include peeling wallpaper, discoloration of
paint, musty odors and condensation in walls and on windows. This can
result in structural damage.
A. Yes, it can.
Trapped inside, air cannot renew itself and
becomes stale. Today's homes are built so tightly that carbon dioxide
(C02) can build up in them. And what is the chief source of carbon
dioxide? It's people — you and your family. Each time you breathe, you
exhale carbon dioxide. And in a tightly built home, carbon dioxide can
build up to an unhealthy level. Add more people and C02 can build up
fast. Symptoms of excess C02 may include nagging headaches, general
lethargy, and grogginess.
If you suffer from frequent colds or allergy symptoms, an HRV can help relieve these problems. In newly constructed homes, pollutants can be released into the air by household chemicals, carpeting and construction materials. These can often be the cause of headaches, asthma, allergic reactions to dust, and the common cold that lingers on in the winter months. An HRV brings in a steady supply of fresh filtered air so that you can breathe easy and safely.
A.
Yes.
The amount of stale air removed and the amount of fresh air
brought in by an HRV are equal so a partial vacuum is not created
in your home. Ordinary exhaust-only systems create a partial vacuum that
pulls radon and water vapor in through pores and cracks in the basement.
Radon causes lung cancer. Condensation of water vapor in cool basements
contributes to growth of molds and other microbes that emit odors and
dangerous volatile organic compounds.
A. You do have a ventilation system in your home if you have a fan in your bathroom or a hood over your range. These are both small units which attempt to solve the problem of removing moist air from the bathroom and hot air and cooking smells from your kitchen. However, these are inadequate for most newly constructed homes and they only solve half the problem: they remove moist air or cooking odors but they draw in replacement air in ways you may not like:
A. Heat recovery ventilators have long been popular in Canada and are becoming popular in the USA. In fact, Canada has a national ventilation law. In 1992 there were more than 125,000 units sold there. In the U.S., there are three states which have ventilation laws and there are more than 15,000 units currently in use in the USA.
A. Most heating, ventilating, and air conditioning dealers can sell and install heat recovery ventilators. Manufacturers include:
United Air Specialists, Inc. (400 to 1,200 CFM)
Energy Recovery Ventilators (save energy and help to control indoor humidity)
