Principles of Make-Up Air
|
|
|
How a make-up air system works
|
Make up air systems replace stale air exhausted from industrial and
commercial buildings with fresh, heated outdoor air, maintaining a
constant leaving-air temperature regardless of the incoming, outdoor-air
temperature.
We offer a direct-fired burner with a turndown
ratio of 30:1 that is 100% efficient - all the heat goes directly into the
airstream. The high turndown capability allows the flame to adjust to wide,
outdoor-air temperature swings throughout heating season. For example, a unit
with a maximum temperature rise of 90 degrees in the winter can adjust down to
as little as a 3 degree temperature rise for milder spring and fall weather.
Make-up air systems replenish equal amounts of fresh air for every cubic
foot of air exhausted. Other types of air-handling systems temper air, but
simply do not offer both the efficiency in operating costs and in fuel
consumption while providing comfort that direct-fired systems deliver.
And, a direct-fired system installs easily -
no vents, flues and chimneys, which means less maintenance.
Finally, make-up air systems solve five major ventilating problems:
- maintains comfort
- controls infiltration
- replaces stale air with fresh air
- prevents negative air pressure
- reduces cold and hot spots
|
|
Is safety a concern?
|
Direct-fired, make-up air is the safe and efficient way to introduce
fresh, make-up air continuously. Mixing fresh air with combustion products
concern some. In fact, contaminant levels from direct-fired heaters are
not only well below recommended, safe levels, but the constant flow-and-exchange
of fresh air removes contaminants well before any significant levels can
accumulate
The Public Health Service and Occupational Safety Health Agency(OSHA) have set
contaminamt-threshold limits for human exposure of carbon monoxide, nitrogen dioxide,
and carbon dioxide - eight hours per day, 40 hours per week without a significant
health hazard.
The chart below compares the current limits established by OSHA with the
combustion by-products of our direct fired unit as tested
by ETL - an independent testing agency.
|
carbon monoxide |
35 |
5 |
nitrogen dioxide |
1 |
0.5 |
carbon dioxide |
5,000 |
4,000 |
|
|