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Title: Ventilation air, the economy cycle, and VAV

Abstract

This article describes a simple yet effective method of providing both minimum and economy cycle control of outside air with a VAV system. Like most of the people in the HVAC industry, the author has been aware that there are problems with ventilation air and economy cycle outside air control when variable air volume (VAV) systems are used. It seemed obvious that the simple solution was to use an injection fan in the outside air intake to provide the minimum ventilation requirement under any operating condition of the VAV system and--presto--the problem would be solved. Recently the author was asked to prepare a seminar on HVAC controls for one of the ASHRAE chapters, with special emphasis on VAV systems. This forced him to take a careful look at the situation, and in the ensuing analysis, it became apparent that the previous look at the problem had not discovered the simplest and perhaps best solution.

Authors:
Publication Date:
OSTI Identifier:
6829442
Resource Type:
Journal Article
Resource Relation:
Journal Name: Heating, Piping and Air Conditioning; (United States); Journal Volume: 66:10
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; BUILDINGS; AIR QUALITY; VENTILATION SYSTEMS; AIR FLOW; VENTILATION; ENVIRONMENTAL QUALITY; FLUID FLOW; GAS FLOW 320106* -- Energy Conservation, Consumption, & Utilization-- Building Equipment-- (1987-)

Citation Formats

Haines, R.W. Ventilation air, the economy cycle, and VAV. United States: N. p., 1994. Web.
Haines, R.W. Ventilation air, the economy cycle, and VAV. United States.
Haines, R.W. 1994. "Ventilation air, the economy cycle, and VAV". United States. doi:.
@article{osti_6829442,
title = {Ventilation air, the economy cycle, and VAV},
author = {Haines, R.W.},
abstractNote = {This article describes a simple yet effective method of providing both minimum and economy cycle control of outside air with a VAV system. Like most of the people in the HVAC industry, the author has been aware that there are problems with ventilation air and economy cycle outside air control when variable air volume (VAV) systems are used. It seemed obvious that the simple solution was to use an injection fan in the outside air intake to provide the minimum ventilation requirement under any operating condition of the VAV system and--presto--the problem would be solved. Recently the author was asked to prepare a seminar on HVAC controls for one of the ASHRAE chapters, with special emphasis on VAV systems. This forced him to take a careful look at the situation, and in the ensuing analysis, it became apparent that the previous look at the problem had not discovered the simplest and perhaps best solution.},
doi = {},
journal = {Heating, Piping and Air Conditioning; (United States)},
number = ,
volume = 66:10,
place = {United States},
year = 1994,
month =
}
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