WHY DO I NEED MAKE-UP AIR?
Modern building codes require homes to be built much “tighter” than in the past. This makes modern
homes much more efficient, but also much easier to depressurize. As a result, today's homes now need a
supply of make-up air, to “make up” for the exhausted air and prevent depressurization.
IAQ or Inside Air Quality is mostly overlooked in these modern homes. Besides the usual “off-gassing” of
the materials used in the construction of the home, the occupant introduces many particulates to the living
space air. Fresh Air is necessary for comfortable and healthy living. Unfortunately, an unavoidable
consequence of daily living is the production of undesirable waste gases, even in small amounts.
Showers produce water vapor, a wide variety of objects off-gas VOC's, gas appliances emit carbon
monoxide, human beings exhale CO
2
. Left to accumulate, these pollutants quickly render a living space
uncomfortable and unhealthy.
Through breathing, carbon dioxide is introduced into the home. Some people wake-up groggy without ever
understanding why, unaware of the level of carbon dioxide in the room they spend their night in. This can
have a measurable influence on the health and well being of the occupants. Not to mention the dust,
viruses, molds, spores and many other airborne particulates which can wreak havoc on the Indoor Air
Quality of your home. AirScape felt something had to be done and with proper filtration and added
functionality to our Make-Up Air Unit managed to handle these issues.
A wide variety of exhausts (e.g. bath fans, dryer fans, kitchen hoods, etc.) are used to expel these pollutants
from the home. However, whenever an exhaust fan is used, fresh air from outside of the living space must
flow into it to replace the expelled air. If this does not happen, the air pressure within the living space
starts to drop relative to the outdoor pressure. This depressurization can have many unpleasant, and even
dangerous consequences: doors open with difficulty and slam shut; dirt, debris, and insects are “sucked”
into the home; pilot lights operate erratically; fireplaces, wood stoves, and combustion appliances
backdraft and toilets bubble sewer gas into the living space.
(“MUA”) is designed to mechanically supply make-up air in residential
applications. Once properly installed, the MUA unit uses pressure sensors to continuously monitor indoor
and outdoor air pressure. When the relative indoor pressure drops below the programmed (settable)
target, a damper opens and the unit's fan dynamically engages, supplying the living space with filtered
fresh air from outdoors. The Make-Up Air unit is controlled with an online web interface which can be
accessed from a computer, tablet or smart phone when the unit is on a local network. The unit's housing is
insulated to maintain the integrity of the home's thermal envelope. To achieve the highest possible
efficiency, the unit's fan is driven by a high-efficiency ECM motor and controlled by a micro processor.
has been modularly designed to be a multi-functional system. The
standard MUA consists of a Cabinet Fan, V-Bank Filter box (MERV13), Air Inlet Selector (damper) and our
sophisticated controller box. The standard unit allows for a multi-functional approach to handling Make-Up
Air and includes fully customizable controller settings that can be easily accessed, operated and read. This
includes a real time Graph Tab which keeps track of the temperatures and pressures in your building.
Besides the always present Make-Up Air Mode the controller interface allows for several other modes. The
Cooling Assist Mode which continuously or periodically (depending on settings) cools the living space by
bringing in fresh Outside Air when the Outside Air is cooler than the Inside Air Temperature. An Air
filtration mode which continuously or periodically filters recirculated Inside Air and an IAQ (Inside Air
Quality) mode brings in filtered Outside Air in adjustable (changeable/settable) proportions improving the
© AirScape MUA-IOM, July 2022, All Rights Reserved.
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