Development of fabricated refrigerant recovery machine for automobile air conditioning system / by Patrick Kier R. Rodriguez and Patrick Dale L. Serquiña.

Design Project (Bachelor of Industrial Technology Major in Automotive Technology) Cavite State University.

Includes bibliographical references.

College of Engineering and Information Technology (CEIT), Department of Industrial Engineering and Technology

RODRIGUEZ, KIER R. and SERQUISA, PATRICK DALE L. Development of
Fabricated Refrigerant Recovery Machine for Automobile Air Conditioning System.
Undergraduate Design Project. Bachelor of Industrial Technology major in Automotive
Technology. Cavite State University, Indang, Cavite. Adviser: Prof. Danielito R. Escano.
Air conditioning is the process of removing heat and moisture or humidity of occupied
space to improve comfort of the occupants. Air conditioning can be used in domestic,
commercial environments, and automobiles. Vacuum is a space in which there is no matter or in
which the pressure is so low that any particles in the space do not affect any processes being
carried on there. It is condition well below atmospheric pressure. One of the equipment that
uses vacuum is the refrigerant recovery machine. The refrigerant recovery machine removes
unwanted air and water vapor from the air conditioning system by the principles of vacuum.
Moisture in air conditioning system is the most problems and complaints. Moisture can freeze
up the air conditioning system and it can also result in corrosion, the effects of which are not
apparent until the real damage has occurred. The refrigerant recovery machine will remove
troublesome moisture by lowering the pressure within the system and vaporizing or boiling of
the moisture. The refrigerant is recovered into a tank for subsequent recycling or reuse.
This study aimed to design, construct and develop a refrigerant recovery machine. The
importance of this study focused on environmental, social and financial aspect of the users. This
machine would lessen the emission of chlorofluorocarbons and hydro chlorofluorocarbons or
also called refrigerant which were very harmful to the environment and to the people. Also, the
machine would give knowledge to the students
on how to use the machine which was needed in their automotive profession.
The materials needed for the machine were purchased and ensured to be in good condition.
The design of the machine was laid out according to its concept. The developers used angular
bar for the construction of the frame and parts bracket. Galvanize metal sheet was used for the
frame cover of the whole machine. There were four skid wheels welded under the machine. The
frame has a dimension of 40cm x 36cm x 90cm. The developers used one horse power window
type compressor as the main component of the machine. It is enough to recover and vacuum
the refrigerant from air conditioning system. Also, there were three receiver driers that would
surely filter the moisture from the refrigerant. The condenser was installed to ensure the
coldness of the refrigerant as it recovers to the recovery tank.
As the refrigerant recovery machine was switch on, the indicator light turned on and the
one horse power compressor immediately runs. The pressure manifold gauge slowly
depreciated as the evacuation process started. The developers observed that the receiver drier
got cold; this indicated that the refrigerant was already flowing into the system of the machine.
The recovery procedure took time as it recovers the refrigerant; it took 10 to 15 minutes to
vacuum the air conditioning system of the automobile. The low side gauge reached the negative
28-29 psi (pounds per square inch). This indicates that the air conditioning system has no leak
and could be able to charge a refrigerant back into the system. The recovery tank was filled up
with refrigerant. It indicates that the refrigerant from the automobile air conditioning system has
been already recovered into the tank of the machine.
The evaluation was conducted by 25 students and 5 instructors with expertise in
automotive air conditioning system. The machine was evaluated according to its functionality,
workability, durability and safety. Based on the results from the evaluation, the machine got 4.8
grand mean which was interpreted as outstanding. It was found out that the machine was useful

and approved by the evaluators and can be use in Automotive Technology Section of the
Department of Industrial Engineering and Technology.
Based on the evaluation and results gathered, the developers recommend improving the
compressor by providing a higher horse power output so that can be used to a bigger
automobile air conditioning system. The developers recommend improving the port of the
common hose by providing a quick release coupling to keep the recovered refrigerant from
leaking when removing the hose. Also, the developers recommend installing a tank capacity
sensor in the recovery tank to monitor the capacity inside the tank.

Submitted to the University Library 08/22/2019 DP-716