Thesis on aircon - improved version

INTRODUCTION
Resource centers such as libraries are constructed to provide safe and comfortable internal study and research environment despite variations in external conditions. Maintenance of a desired interior condition in research centers without having high costs of expenditure is relied upon on a good building design and an air-conditioning design.
The primary intent of this study is to come up with appropriate air-conditioning designs that will intimately maintain good air quality and controlled temperature even during peak loads.
Cebu State College of Science and Trade is applying an accreditation to declare for a constant attunement of curricula. Accreditation is basically an inspection of the curriculum design, achievements of the school and the physical set-up.
Offices and Resource centers are not spare with the inspection. It is expected that centers inside the school will come up to the expectations of the inspectors.
The Library is the center of the academe. It is one of the important centers inside an academic institution. It is the venue to seek information and data on various issues and topics. Its provisions will include vehicle for data gathering and hall for studying purposes.
Ventilation for such centers is a compelling requirement not only to provide comfort to those who will choose to stay and study but to enhance the protection of library materials for longer usage. Air conditioning with its salient features such as controlling humidity will prevent the library materials to wear out.
The installation of a unit in the library will deface the possibility of the wearing out of library materials and may be a good attribute to a possible accreditation next school year.
OBJECTIVES OF THE STUDY
This study will be conducted to come up an installation design for air-conditioning units to be installed at the library of the Cebu State College of Science and Technology, Cebu City campus. Specifically, this study will be aimed to:
a. Determine the average number of users and the peak
hours of use.
b. Categorize the materials or equipments of College of Science and Technology-Main Campus Library.
c. Calculate the area for the installation of air-conditioning units.
d. Identify the type of units to be installed at the College of Science and Technology-Main Campus Library.
CHAPTER I
THEORITICAL FRAMEWORK
This chapter presents the relevant literature and studies conducted which are essential in the development of the conceptual and in providing directions for the study.
REVIEW OF RELATED LITERATURE
The primary objective of air-conditioning is to provide comfortable conditions of the people. From the thermal standpoint, the body is inefficient machine but a remarkably good regulator of its temperature. The human body receives full in the form of food, converts a fraction of the energy in the fuel into work, and rejects in the remainder as heat. It is the continuous process of heat rejection, which requires a thermal balance. The generation of heat occurs in cells throughout the body, and the circulatory system carries this heat to the skin, where it is released to the environment.
In a steady-state heat balance, the heat energy produced by metabolism equals the rate of heat transferred from the body by convention, radiation, evaporation and respiration.
If the metabolism rate is not balanced momentarily by the sum of the transfer of heat, the body temperature will change slightly.
Most people felt restless and uncomfortable if heat wrapped up the body. Concentration is destroyed and work is not organized.
The library is the place where most researchers meet. Some of them are cramming for some information needed to be researched. There are times when the library experienced constraints in terms of occupancy. White space is hard to find and the direct object to this is the warming of the whole area.
The surface area of the body is usually in the range of 1.5 to 2.5 m², depending upon the size of the person.
The heat-transfer coefficient depends upon the air velocity across the body and consequently also upon the position of the person and orientation to the air current.
Based on the discussion made by W.F. Stoecker which are properly dished out in his book Refrigeration and Air-conditioning, the skin temperature is controllable to a certain extent by the temperature-regulating mechanism of the body covered by clothing.
The clothing temperature will normally lie somewhere between the skin and the air temperature, unless lowered because it is wet and is evaporating moisture.
The human body is an adaptable organism. With long-term conditioning the body can function under quite extreme thermal conditions. Variations in outdoor temperature and humidity, however, go beyond the normal limits of adaptability, and it becomes necessary to provide modified conditions indoors in order to maintain a healthy, comfortable environment.
The body is continuously generating heat, which must be dissipated to maintain a constant body temperature.
For a person at rest of doing light in a conditioned space, the body dissipates heat primarily by convection (carried away by the surrounding air) and radiation (to surrounding surfaces that are at a lower temperature than the body temperature).
Most of the air-conditioning units in service provide comfort air conditioning, the purpose of which is to supply comfortable conditions for people. Summer cooling systems have become a standard utility in large buildings throughout the world. Even in climates where summer temperatures are not high, large buildings may have cooled in order to remove the heat generated internally by people, lights, and other electrical equipment. In hot climates, the existence of summer cooling systems is the difference between workers performing effectively and not.
This chapter does however, attempts to present the importance of air-conditioning to establishments, service areas and institutions.
Air conditioning embraces more than cooling. The definition of comfort air conditioning is “the process of treating air to control simultaneously its temperature, humidity, cleanliness and distribution to meet the comfort requirements of the occupants of the conditioned space” .
Air conditioning of medium-sized and large buildings. Most of the air-conditioning units in service provide “comfort air conditioning”, the purpose of which is to supply comfortable conditions for people. Even in climates where summer temperatures are not high, large buildings may have been cooled in order to remove the heat generated internally by people, lights, and other electrical equipment.
Computer rooms. The air conditioning system for computer rooms should control the temperature, humidity, and cleanness of the air. Some electronic components operate in faulty manner if they become too hot, and one means of preventing such localized high temperature in the computer room in the range of 20 to 23ºC. The electronic components in the computer function favorably at even lower temperatures, but this temperature is a compromise with the lowest comfortable temperature for occupants.
Residential air conditioning. In United States, approximately 5 million room air conditioners are sold each year, and most of them are used for residential service. Control of humidity is one of the primary reasons for air conditioning. There are several materials that are sensitive to changes in humidity and to a lesser extent changes in temperature. The role of air conditioning varies from one environment laboratory to another. Its role varies also from one job environment to another. For manufacturers of precision metal parts, air conditioning performs three services.
1. Keeping the temperatures uniform so that the metal
will not expand and contract.
2. Maintaining a humidity so that the rust is
prevented.
3. Filtering the air to minimize dust.
ASHRAE Trans., vol. 85 have elaborated the facts that
heat transfer have developed from a general set of concepts, based on observations of the physical world, the specific models, and laws necessary to solve problems and design systems. Mass and energy are two of the basic concepts from which engineering science grows.
As the physical world is extremely complex, it is virtually impossible to describe it precisely. One of the most significant accomplishments of engineering science has been the development of models of physical phenomena, which although they are approximations, provide both a sufficiently accurate description, and a tractable means of solution.



SYNTHESIS
The related literature and studies included in this study bearing the development of the conceptual framework. This study on the proposed installation of an air-conditioning unit in Cebu State of Science and Technology Main Campus library likewise moved into giving students a conducive area to study and providing a good chance for the school to edge ahead in facilities.
As intended by other studies conducted, this study also attempted to provide ample idea for the implementers to consider in the enhancement of the school’s layout.
CONCEPTUAL FRAMEWORK OF THE STUDY
The review of related literature and studies cited that design conditions of air-conditioning systems are not isolated. The estimation process includes assessment of the context, the inputs, the process and products of the organizations. These variables should inter-relate with one another in order to achieve clearly stated development goals.
The design conditions usually specified for estimating heating loads are the inside and outside dry-bulb temperatures. The set of conditions specified for cooling-load estimates is more complex and includes dry-bulb temperature, humidity and solar intensity. Variables of these kinds vary in different situations and conditions.
The Context Input Process Product Model (CIPP) Stufflebeam approach to evolution is rooted in its definition of evaluation as the process of deliberating, obtaining and providing useful information for judging decision alternatives. This model has four types of educational decisions namely:
1. planning decisions to determine objectives
2. structuring decisions to design instructional procedures.
3. implementing decisions to use, monitor and improve these procedures and
4. recycling decisions to judge and react to the outcome produced by these procedures
For each of these different types of decisions, a corresponding type of evaluation is recommended namely: context, input, process and product. This form of evaluation is the heart of the CIPP Model (Pophan, 1974). Hence, this study hinges on the CIPP Model using it as its conceptual framework.
Context evaluation is the most basic kind of evaluation used in this study. It runs down to every detail accumulated in the process of the research.
Input evaluation was then applied to get into the basic calculations to come up with the necessary data used in the exploration and propagation of the study.
Process evaluation was used to get the specific answers to the inquiries presented in this research to be able to get the fitted design of an air-conditioning unit to be installed in the Cebu State of Science and Technology Library.
In the context of this study, the inputs included the following funding, objectives, curriculum, administration, research, students, facilities and equipments.
The input explained above determines the process, which was divided into qualitative and quantitative outputs.
The input and process largely determine the product.
SIGNIFICANCE OF THE STUDY
The proposed installation of an air-conditioning unit in Cebu State of Science and Technology library will enhance usage of the library and the protection of the library materials. This will also provide a better chance for the library to come out with a good ranking for AACUP accreditation. Hence, this will help the College to gain an opportunity to gain better appraisal from accreditors.
We do believe that by the presence of the an air conditioning unit in the library more students will be encourage to avail of the service the research center could offer.
This, on the other hand can minimize the depreciation of the library materials such as books, journals and periodicals. This will eventually give these items a higher utility rate.
SCOPE AND LIMITATIONS
This study was focused on a proposed installation of an air-conditioning unit in which the group to come up with a better type of the unit to be installed studies salient features and design. The proposal was concerned itself with the study of existing clamor of students and frequent users of the library regardless of profession to the present condition of the library in relation to ventilation. It included the study of possible objectives that might be formulated for installation of the unit as well as the formulation and calculation of data to get the fitted unit that will be installed in the library.
The investigator limited the researches to be conducted during the months of July to October, which are basically school days to augment the necessary data to be gathered.
This study does not cover a wider scope of air conditioning. It merely focused on the data gathering and analysis to come with the type of unit that is fitted in the type of place to be conditioned such as College of Science and Technology-Main Campus Library. It does not seek to include the study of the volumetric, cooling and dehumidifying areas of air conditioning. It will only deal on the basics of heating and cooling-load calculations.
The coverage is not that wide for the span of time given to conduct this study is short and limited taking into account the various hindrances the researchers would have to face.








RESEARCH DESIGN
Experimental, Historical and Descriptive Methods of Research were used in this study. The descriptive method is a general procedure employed in studies that have their chief purpose description of the phenomena. The description of the existing problems encountered in the library in relation to its application for accreditation and general usage, its facilities, standard used, researches and survey of the proposed place to be conditioned were therefore the primary tasks of this study.
Experimental method was applied during which the researches devoted their time calculating the peak loads of their target site. It was the time when researches employed research strategies away from the laboratory conditions. Experimentations were made to come up with the specific designs for a system to be installed of the target place to be conditioned.
Historical method is a useful design, which involves critical writing of past experiences, events and developments in order to provide helpful information and direction for present and future action.
The method was used by the group to convey that an installation of an air-conditioning unit in centers like the library is a very salient factor in coming up with positive results in regards to study enhancement, provision of comfort air-conditioning and the like. This method will shed light on the issues, which will eventually lead to the discovery of the truth and enrichment of knowledge.
RESEARCH LOCALS
The respondents of this study were obtained from the heads, faculty members, and concerned students of Cebu State of Science and Technology – Main Campus.














DEFINITION OF TERMS AND VARIABLES
The following is a list of terms that will be used in this study:
Air distribution. A crucial design requirement in handling the air properly within the conditioned space.
Blackbody. Perfect radiator.
Comfort air conditioning. Provision of comfortable conditions for people.
Dehumidifiers. An appliance to dehumidify air in homes and buildings.
Industrial air conditioning. Provision of at least a partial measure of comfort for workers in hostile environments but also to control air conditions so that they are favorable to processing some object or material.
Infiltration. Heat loss or heat gain due to the infiltration of outside air into a conditioned space.
Internal. Heat gain due to the release of energy within a space (lights, people, equipment, etc.)
Solar. Heat gain due to the transmission of solar energy through a transparent building component or absorption by an opaque building component.


CHAPTER II
RESULTS, DISCUSSION AND INTERPRETATION OF DATA
Energy Required for Cooling
Name: Cebu State College of Science and Technology, Main
Campus R. Palm St., Cebu City
Phone:
Use of Space: Library
I. Interior Room Dimensions:
Length: 64 feet Width: 52 feet Height: 10 feet
Windows:
Table 1
Facing
No of Windows
Sizes
South
4
5’2” x 3’8”
East
6
5’2” x 3’8”
West
8
5’2” x 3’8”
Total Area = 18 x 5’2” x 3’8” = 341 ft2
Doors:
Table 2
Facing
Sizes
Area
South
7’ x 8’
56 ft2
North
12’ x 8’
96 ft2
East
3.5’ x 8’
28 ft2

Door Type: Glass Door with Aluminum Frame
Total = 180 ft2


II. Heat Contributors:
Table 3
Contributors
No.
Electrical Data
People
128
None
Personal Computer
(desktop)
3
None
Impact Printer
3
None
Laser Printer
2
None
Copier
2
None
Fluorescent Lamp
28
35 Watts (Input)

Walls and Partitions
Table 4
Facing
Sizes
Area
South
66’ x 10’
660 ft2
North
52’ x 10’
520 ft2
East
76’ x 10’
760 ft2
West
64’ x 10’
640 ft2

Total = 2, 580 ft2
Note: The total area of the wall using this dimensions will be subtracted by the total door and window area.
III. Formulas and Data
A. For external load sources such as roofs, walls, glass (conduction), partitions, ceilings and floors.
Q = U x A x CLTD
Where:
Q = Design Cooling Load
U = Design Heat Transfer Coefficient
A = Area Calculated from Architectural Plans
CLTD = Cooling Load Temperature Difference
B. For Solar source
Q = A x SC x SHGF x CLF
Where:
Q = Design Cooling Load
A = Net Glass Area Calculated from Plans
SC = Shading Coefficient
SHGF = Solar Heat Gain Factor
CLF = Cooling Load Factor
C. For internal load sources
C-1. For Lights
Qef = watts x 3.42 x 1.25
Where:
Qef = gain from fluorescent lightning
C-2. For People
Sensible Qs = No. x Sens. H.G. x CLF
Latent Ql = Heat Gain
Where:
Q = Design Cooling Load
No. = No. of People
Sens. H.G. = Sensible Heat Gain
CLF = Cooling Load Factor
C-3. For Appliances and Equipment
Q = Heat Gain
D. Ventilation and Infiltration Air
Sensible Q = 1.10 x CFM x (to – ti)
Latent Q = 4840 x CFM x (Wo – Wi)
Where:
CFM = cubic feet per minute; volumetric flow of air
to & ti = Inside-Outside Air Temperature Difference, oF (oC)
Wo & Wi = Humidity Ratio, kgm / kga
IV. Cooling-Load Calculations:
A. Walls
Actual Wall Area = 2, 580 ft2 - 341 ft2 – 180 ft2 = 2, 059 ft2
q From Table 4E, Coefficients of Transmission (U) of Masonry Cavity Walls, (Chapter 23 of ASHRAE Handbook)
For Construction No. 1: U = 0.204
q From Table 4F, Coefficient of Transmission (U) of Masonry Partitions
For Construction No. 1: U = 0.308
q From Table 7-3, Design Temperature Difference (Section 7 of HVAC Design Data Source Book)
For Exterior Walls: CLTD = 17 oF
Therefore:
Q = U x A x CLTD = 0.204 BTU/hr.ft2.oF x 2,059 ft2 x
17 oF
Q = 7, 140.612 BTU/hr.
B. Glass
Total Window or Glass Area = 341 ft2
q From Table 13, Part A (Chapter 27 of ASHRAE Handbook)
For single clear glass with indoor shade and without storm sash, for summer: U = 0.81 BTU/hr.ft2.oF
q From same table, Part C Adjustment Factors (AF) for Various Windows; (same book)
For single glass with metal frame: AF = 1.0
q From Table 10, CLTD for Conduction through Glass; (Chapter 26 of same book)
For solar time of 12 hours: CLTD = 9 oF
Therefore:
Q = U x A x CLTD = 0.81 BTU/hr.ft2.oF x 341 ft2 x 9 oF
Q = 2, 485.89 BTU/hr.
Total door area = 180 ft2
q From Table 7-3, Design Temperature Differences; (Section 7 of HVAC Design Data Source Book)
For Glass in Partitions: CLTD = 10 oF
Therefore:
Q = U x A x CLTD = 0.81 BTU/hr.ft2.oF x 180 ft2 x 10 oF
Q = 1, 458 BTU/hr.ft2.oF
Total:
Q = (2,485.89 + 1,458) BTU/hr. = 3,943.89 BTU/hr.
C. Solar
Total Glass Area = Window Area = 341 ft2
q From Table 4-11 in Chapter four, Book of Ref. and Air Conditioning
For single plate glass, 6-12 mm. Thick with Venetian Blinds: SC = 0.64
q From Table 11 Solar Heat Gain Factor for Glass; (Chapter 26 of ASHRAE Handbook)
SHGF = 271 BTU/hr.ft2
q From Table 14, Cooling Load Factor if Interior Shading is Used; (same book)
For Solar time of five hours: CLF = 0.07
Therefore:
Q = A x SC x SHGF x CLF
Q = 341 ft2 x 0.64 x 271 BTU/hr.ft2 x 0.07 =
4,140.0128 BTU/hr.
D. Partitions, Ceilings, and Floors
Total Floor and Ceiling Area = (64 x 52) ft2 – 147 ft2 = 3, 181 ft2
q From Table 4H, Coefficient of Transmission (U) of Masonry Ceilings and Floors; (Chapter 23 of ASHRAE Handbook)
For Construction No. 2: U = 0.112 BTU/hr.ft2.oF
q From Table 7-3 Design Temperature Differences; (HVAC Design Data Source Handbook)
For floors above unconditioned rooms: DTD = 10 oF
For ceilings with unconditioned room above:
DTD = 10 oF

Therefore:
Q = U x A x CLTD
Q = 0.112 BTU/hr.ft2.oF x 3,181 ft2 x 10 oF
Q = 3, 562.72 BTU/hr.
This calculated heat load would be multiplied by two for floor and ceiling.
Q = 2 (3,562.72) BTU/hr. = 7,125.44 BTU/hr.
E. Lights
No. of Fluorescent Lamp = 28 @ 35 watts
Therefore:
Q = (Watts x 3.42 x 1.25) No. of lights
Q = (35 watts x 3.42 x 1.25) 28
Q = 4, 189.5 BTU/hr.
F. People
No. of People in the space = 128
q From Table 18, Rates of Heat Gain from Occupants of Load Spaces; (Chapter 26 of ASHRAE Handbook)
Degrees of Activity
Typical
Application
Sensible Heat
BTU/hr.
Latent Heat
BTU/hr.
Seated, light work, typing, writing
Offices, Hotels, Libraries

285

255

q From Table19, Sensible Heat Cooling Load Factor for People; (Chapter 26 of ASHRAE Handbook)
Total Hour in Space
Cooling Load Factor
Hours after each entry
2
0.58
2

Therefore:
For Sensible Qs = No. x Sens. H.G. x CLF
Qs = 128 x 285 BTU/hr. x 0.58
Qs = 21, 158.4 BTU/hr.
For Latent Ql = 128 x 255 BTU/hr.
Ql = 36, 480.0 BTU/hr.
Total:
Q = (21,158.4 + 36,480) BTU/hr.
Q = 57,638.4 BTU/hr.
G. Equipment
From Table 7.4, Typical Heat Gain Rates for Several Kinds of Equipments; (Chapter 7 of Heating and Cooling of Buildings Book)
Equipment
Heat Gain
Comments
Personal Computer
(Desktop)
170-680

Impact Printer
34-100 (Standby)
Increase about two folds during printing
Equipment
Heat Gain
Comments
Laser Printer
510 (Standby)
Increase about two folds during printing
Copier
500-1000 (Standby)
Increase about two folds during printing

Note: Use the maximum range of heat gain and assume the equipments are on operation for the maximum calculation of loads.
Therefore:
Qpc = 680 BTU/hr. x 3 =2,040 BTU/hr.
Qip = 100 BTU/hr. x 3 x 2 = 600 BTU/hr.
Qlp = 510 BTU/hr. x 2 x 2 = 2,000 BTU/hr.
Qc = 1000 BTU/hr. x 2 x 2 = 4,000 BTU/hr.
Total = 8,640 BTU/hr.
H. Ventilation and Infiltration Air
q From Table 7-8 Cooling Load High Check Figure
Building Classification
Occupancy,
ft2 / person
Air Quantities
cfm / ft2
Libraries & Museums
40
1.4

Therefore:
CFM = Air Quantities x Occupancy
CFM = 1.4 cfm/ft2 x 40 ft2/person = 56 cfm/person
q Base from the record shown of Cebu PAG-ASA Complex Climatology Normals (1973-2001). The highest record of temperature of Cebu during summer is 96.8 oF with a Relative Humidity of 75%.
q Base from the Air-conditioning standards, if a person is wearing appropriate clothing, the following ranges should usually be acceptable:
Operative temperature. 68 to 78.8 oF
Humidity. A dew-point temperature of 35.6 to 62.6 oF
Therefore:
For Sensible Qs = 1.1 x CFM x (to – ti)
Qs = 1.1 x 56 cfm/person x (96.8 – 68) oF
Qs = 1774.08 BTU/hr.
q From Table 4-Recommended Inside Design Conditions-Summer (Part 1 Chapter 2 of Air Conditioning System Design Handbook)
For General Comfort: Dry Bulb Temperature – 77-79 oF
Relative Humidity – 50-45%
q Use Psychometric chart in order to get the humidity ratio difference by plotting the dry bulb temperatures and relative humidity.

For outside temperature of 96.8 oF & Relative Humidity of 75%:
W = 0.029 kgm/kga
For inside temperate of 68 oF & Relative Humidity of 50%:
W = .0057 kgm/kgs
Therefore:
Ql = 4840 x CFM x (Wo – Wi)
Ql = 4840 x 56 cfm/person x (0.029 – 0.0057) kgm/kga
Ql = 6,315.232 BTU/hr.
Total:
Q = (1,774.08 + 6315.232) BTU/hr.
Q = 8,089.312 BTU/hr.
V. Total Cooling Loads
Load Sources
Calculated Loads
BTU/hr.
Walls
7,140.612
Glass
3,943.89
Solar
4,140.0128
Partitions, Ceilings & Floors

7,125.44
Lights
4,189.5
People
57,638.4
Equipment
8,640
Load Sources
Calculated Loads
BTU/hr.
Ventilation and Infiltration Air

8,089.312

Total = 100,907.17 BTU/hr.
q If by Tons of Refrigeration

Total Heat Load = (100,907.17 BTU/hr.) / (912,000 BTU/hr.)
Total Heat Load = 8.4089 Tons of Ref.
q For Cooling Capacity of the Unit
Cooling Capacity = 9 TR (108,000 BTU/hr.): if the unit will be use is having 3 TR (36,000 BTU/hr.) of cooling capacity each.
Cooling Capacity = 10 TR (120,000BTU/hr.): if the unit will be use is having 5 TR (60,000 BTU/hr.) of cooling capacity each.
VI. Specifications of the Unit
Type of Air-Conditioning Unit: Ceiling Exposed Type (Split Unit)
Cooling Capacity of the Unit: Either 3 TR (36,000BTU/hr.) or 5 TR (60.000 BTU/hr.)
No.of Units: Three units, if 3 TR is to be installed
Two units, if 5 TR is to be installed
CHAPTER III
SUMMARY AND CONCLUSION
SUMMARY:
It was the main purpose of this study to determine the feasibility of the installation of an air-conditioning unit for the library in Cebu State of Science and Technology- Main Campus Library. Specifically; the study involved the following problems:
1) How did the study of the existing problems confronting the library users of the Cebu State of Science and Technology Library- Main Campus help in the coming up of the study for the installation of an air-conditioning unit?
2) What procedural objectives may be formulated in the installation of the air conditioning unit?
3) What standards could be established for the installation of the unit?
a) design
b) site
c) personnel involved
d) cost
4) What other problems that might be eased out in the existence of a conditioning system in the library most specifically on the effects of the installation to the application for an accreditation of the college?
5) What possible input would the proposal create in improving the ratings of the school in AACUP accreditation schema?
Recommendations:
On the basis of the findings of this study, the researchers recommends the following which are indispensable in the installation and maintenance of an air-conditioning unit in the library of Cebu State of Science and Technology- Main Campus. Backed up by strong feasibilities of the study, the researchers were able to come up with the following possibilities:
q It is very advisable and better to put indoor shading for windows like Venetian blinds, curtains and etc., in order the solar heat cannot directly penetrate to the space to be conditioned. By this way we can minimize the operating cost since it reduces the heat load or added to the conditioned space.
q A glass door will be put to the door openings facing south and north in order to prevent too much infiltration of air, which can contribute a lot of heat load that leads to the discomfort of the occupants. Other way of preventing this infiltration of air is to put an air curtain, which could be strategically be located inside and above the door opening, this would only be used when the door is permanently open during the usage of the conditioned space.















REFERENCES:
ASHRAE Handbook; McGraw Hill Book Company, 1965.
“Environmental Control in Industrial Plants”, Symp.,PH79-1, ASHRAE Trans, vol.85, p.30, 1979.
Handbook of Air Conditioning System Design; McGraw Hill Book Company, 1965.
Kreider, Jan F. and Ari Pabl. Heating and Cooling of Buildings; Design for Efficiency, 1964.
Parmley, Robert O. HVAC Design Data Source Book, 1994.
Stoecker, Wilbert F. Refrigeration and Air Conditioning: 2nd ed., 1964.