Development of empirical temperature and humidity-based degraded-condition indicators for low-tonnage air conditioners /

(STO), or fixed-orifice expansion, and a system that uses a

Bibliographic Details
Main Author: Watt, James Bonner
Format: Thesis eBook
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1997.
Subjects:
Online Access:Link to OAKTrust copy
Description
Summary:(STO), or fixed-orifice expansion, and a system that uses a
A split-system direct-expansion air conditioner was used to
an important factor for obtaining early detection over a wide
automated detection systems for failures and degraded
based approach. It sought to utilize only low-cost
bench was equipped with the ability to use either a short-
charge and a blocked condenser coil were not studied.
conditions of low-tonnage air conditioners. The effects of
degraded conditions studied include low evaporator airflow,
depend on three loading factors; outdoor-air temperature,
detect degraded conditions without regard to the expansion
device.
differentiated between a system that uses a shorttube orifice
empirically determine temperature and return-air humidity
high and low-charge, and a blocked condenser coil. The work
identify degraded effects that fall outside of a simulation-
indicators that could detect performance degradation
is also shown that indicators of low evaporator airflow
literature, the humidity sensing point has been neglected by
presented in this thesis is experimentally based which could
range of operating conditions. It was empirically based
rather than model based to reduce computation time with a
real-time processor. Further, the current work
resulting from degraded conditions. The air conditioner test
return-air temperature, and return-air humidity. In the
STO system and a TXV system relative to the degradations
studied, a common set of indicators was identified that could
temperature sensing means, although return-air humidity was
the loading factors on the indicators relative to improper
thermal expansion valve (TXV), or variable-orifice expansion.
This thesis shows that low-cost temperature sensors could be
tube orifice (STO) or a thermal expansion valve (TXV). The
used to detect the degraded conditions studied. However, it
Item Description:"Major subject: Mechanical Engineering".
Vita.
Physical Description:xxi, 184 leaves : illustrations ; 28 cm.
Also available online.
Issued also on microfiche from Lange Micrographics.
Bibliography:Includes bibliographical references: pages 165-171.