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Controlling Ventilation Air Flows
Animation Series 1:
Controlling Ventilation Air Flows
- Desired Ventilation Flows
- Overcrowded Offices
- Air Handling Unit Contaminated
- Outdoor Air Damper Opening Reduced
- Exhaust Not Operating Properly
- Supply Air to Office Shut Off or Pinched Down
- Economizer Operating
- Contaminated Outdoor Air
Economizer Operating
Mouse over the animated picture above to see messages which are referenced in more detail below.
Pressure relationships between rooms is designated at the bottom of each room (with a plus for positive and minus for negative pressure).
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[OUTDOOR AIR] The weather is cool outside. So the economizer is bringing in large quantities of outdoor air to provide “free cooling”. Humidity is also being carefully controlled. How does increased outdoor air effect pollution levels in the building?
- [OCCUPIED SPACE] The increased outdoor air flow from the economizer provides greater dilution of indoor generated contaminants in occupied spaces. However, indoor concentrations of outdoor contaminants has slightly increased. As suggested in the picture, except in cases where the outdoor air is highly contaminated, the net effect of increasing outdoor air flow is usually to lower indoor air pollution.
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