Brochure

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With houses and buildings being built as
tightly as possible, we are plagued by
unbalanced ventilation systems.
This means we can have positive air
pressure caused by exhausted air not
being ventilated as fast as supply air
comes in. Or, vice versa. There can
be negative pressure with supply air
not being brought in as fast as air is
exhausted.
This leads to too much moisture in the
home or building and increased loads
on the heating and cooling system. Poor
ventilation can also cause unpleasant
odors and buildup of contaminants such
as radon, formaldehyde, and VOCs.
Unbalanced Pressure, Inefciency, Moisture, and Toxins
Common Ventilation Issues for
Homes and Light Commercial Buildings
Sensible Heat
The amount of energy involved in raising or lowering the temperature of air not including any energy required to cause
water vapor to change state.
Latent Heat
The amount of energy associated with the humidity (or water vapor content ) of an air stream. A drier air stream contains
less latent heat and will impose a smaller latent load on the air conditioner.
Enthalpy
The total amount of energy contained in air, the sum of sensible and latent heat.
Balanced Ventilation
A ventilation strategy using both an exhaust air blower and a supply or make-up air blower that does not pressurize or
de-pressurize a building.
Air-to-Air Heat Exchanger
Generic term for technologies designed to transfer heat -- and sometimes moisture -- between two air streams.
Heat Recovery Ventilator – HRV
An air-to-air heat exchanger that transfers sensible heat only; no humidity (latent heat) transfer occurs between the two
air streams.
Energy Recovery Ventilator – ERV
In Cold Weather, some of the humidity in the inside air is recovered – along with its latent energy. Non-enthalpic heat
recovery systems lose that latent energy.
Terms to Know
Supply Only Fan
Application
Exhaust Only Fan
Application
Positive air pressure
Forces hot and/or humid air
into walls and insulation.
Negative air pressure
The unltered air increases
risks of mold and causes
energy costs to be higher.