Outdoor air flow control for VAV systems
- Johnson Controls Inc., Milwaukee, WI (United States)
Controls for variable air volume (VAV) systems must assure a minimum outdoor air flow rate for space pressurization. ASHRAE Standard 62-1989 places additional emphasis on the outdoor air flow to assure adequate ventilation. Economizer controls also vary outdoor air flow to maintain discharge air temperature. In VAV systems, meeting these multiple outdoor air flow-related requirements presents some significant control challenges. This article focuses on VAV central system controls and shows how online outdoor air flow measurement and control can be used to assure ventilation as well as meet space pressurization requirements. A novel method for online outdoor air flow measurement is recommended and a control strategy that integrates the multiple requirements for providing outdoor air is described.
- OSTI ID:
- 62999
- Journal Information:
- ASHRAE Journal, Journal Name: ASHRAE Journal Journal Issue: 4 Vol. 37; ISSN ASHRAA; ISSN 0001-2491
- Country of Publication:
- United States
- Language:
- English
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