This document describes a localized miniature air handling unit (AHU) that is a simple device consisting of a heating/cooling coil and fan. It can control the temperature in a single space or multiple spaces. Compared to central AHUs and air conditioners, these units are more economical to install due to their simplicity and flexibility. The document discusses the working principle and design of miniature AHUs, as well as advantages over central AHUs like localized control and energy efficiency. It also notes potential advantages over split air conditioners like energy efficiency and no refrigerant leaks.

1. Design and Implementation of Localized Miniature AHU
Kavish Jadwani, Ronnit Roy Burman| Prof. Uma Sathyakam.P| SELECT
A localized miniature AHU is a simple device consisting of a heating and cooling
heat exchanger or 'coil' and fan. It will form a part of an HVAC system and can be
used in residential, commercial, and industrial buildings. It can be used with a
ductwork, and is useful to control the temperature in the space where it is
installed, or serve multiple spaces. Due to their simplicity and flexibility they
seem to be more economical to install than AHUs and air conditioners.
Working Principle
The localized miniature AHU will work on the basic refrigeration cycle a
Design and Operation
A miniature AHU will be installed within a service zone. The coil receives hot or
cold water from a central plant, and removes heat from or adds heat to the air
through heat transfer. It can contain its own internal thermostat or can be wired
to operate with a remote thermostat or it can be used with a Building Energy
Management System (BEMS) where the control of the AHU unit will be by a local
digital controller. Cold and hot water is generated at a chiller or a cooling tower
and at boiler or a commercial water heater respectively.
Advantages of AHUs
AHU’s are highly energy efficient compared to electric AIR Conditioners
AHU’s provide comfortable indoor conditions thus increasing productivity.
 Clean air supply thus maintaining better health.
It provides centralized control It has no risks of leakage of refrigeration gases.
Problem with AHU’s
Though AHU is energy efficient but it has extremely high installation cost.
 It does not provide a localized control
It is economical only when the space is completely occupied.
It is not comfortable in situations where there are large number of small zones.
It causes mixing of air.
Advantages of Split Air Conditioners
Ductless and Small size
Flexibility: great for zoning or the heating and cooling of individual rooms
Better localized control.
Capable of saving you energy and thus saving you money
Avoid energy loss associated with ductwork, which can account for up to 30% of
energy consumption
Problems with Split Air Conditioners
 Extremely high energy consumption
High risk of leakage of refrigeration gases.
Probable Advantages of Miniature Localized AHU
Energy Efficient : Since it uses the same installation as of AHU , thus it is energy
efficient compared to the electric air conditioners.
Providing Localized Control : It is Economical even when space is not completely
occupied and provides localized control for each zone.
Most suitable for small zones.
No mixing of Air
NO risk of refrigerant leaks in the building.
SCOPE of the Project
Results
Localized Miniature AHU
Our project "Design and Implementation of Localized Miniature AHU" is an
initiative to identify, explore and develop possible alternative models to improve
the Air Conditioning and Ventilation industry in the future. The project aims to
evaluate the risks and disadvantages of various existing air conditioning options.
The alternative model explored and proposed by the team will attempt to move
away from the current approach and aims at transforming disadvantages of
traditional methods into an advantage.
An AHU or Air Handling Unit is a complex device that is used to condition and
circulate air as a part of Heating Ventilation and Air Conditioning Systems (HVAC).
AHU is a huge metal box containing a blower or fan, heating or cooling coils, filter,
dampers etc and is usually connected to centrally located chillers and boilers and
distributes the conditioned air through the building through ductwork. Air
conditioners are powerful and flexible ways to cool a localized zone. Both AHU
and Air Conditioners have some advantages and some disadvantages. Our concept
of miniature localized AHU aims at designing a simple yet flexible device capable
of heating , cooling and dehumidification. The main objective is localized control.
Motivation/ Introduction
As part of our final year project we designed a miniature localized AHU and we
presented a proof of concept. The model is a very simple demonstration of the
concept of localized miniature AHU.
We strongly believe that with further research and work on this concept will
increase the efficiency of the localized AHU and in recent years we can hope to
see such units in commercial and domestic buildings
Acknowledgments/ References
[1] "HVAC," in Wikipedia, Wikimedia Foundation, 2016. [Online]. Available:
https://en.wikipedia.org/wiki/HVAC. Accessed: Apr. 30, 2016.In-line Citation:[1]
[2] "Air handler," in Wikipedia, Wikimedia Foundation, 2016. [Online]. Available:
https://en.wikipedia.org/wiki/Air_handler. Accessed: Apr. 30, 2016.In-line
Citation:[2]
[3] "HVAC". Merriam–Webster Dictionary. Retrieved 2015-01-12.
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New York, 2002
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Systems," Ashrae Trans., vol 107(2):346-352, 2001.
[6] Ahn, Mitchell, McIntosh, "Model-Based Fault Detection and Diagnosis for
Cooling Towers," Ashrae Trans., vol 107(1):839-846, 2001
[7] Jerome Adnot, Julien Caillet, Mohamed Delleci and Philippe Riviere Armines,
"Energy Conservation Opportunities for Air conditioning Systems"
[8] Norman C. Harris, McGraw-Hill International Edition
[9] Kurt W. Roth, Detlef Westphalen, John Dieckmann, Sephir D. Hamilton and
William Goetzler, "Energy Consumption Characteristics of Commercial Building HV
AC Systems", vol. III
[10] "Energy Consumption Characteristics of Commercial Building HV AC Systems",
Detlef Westphalen and Scott Koszalinski
[11] A. Bhatia, "A guide to Heating and Cooling Load Estimation"
Conclusion and Future Work
Contact Details
Kavish Jadwani : jadwanikavish.rajesh2012@vit.ac.in
Ronnit Roy Burman: ronnitroy.burman2012@vit.ac.in
Fig1: Block Diagram of Miniature Localized AHU