[Tex/LaTex] How to change font size of chapter to 14pt

Question

By default the fontsize of chapter is 25pt. I want to change it to 14pt.

Here is the code that I'm running to generate the pdf. I have downloaded this format. Its not my format so I'm little confused how to change the font size to 14pt.

\documentclass[12pt,a4paper]{report}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage[pdftex]{graphicx} %for embedding images
\usepackage{url} %for proper url entries
\usepackage[top=1in,bottom=1in,left=1.3in,right=.60in,a4paper]{geometry}
\renewcommand{\baselinestretch}{1.5}
\usepackage[nottoc]{tocbibind}
\usepackage{sectsty}
\usepackage[T1]{fontenc}

\usepackage{etoolbox}
\makeatletter
%\patchcmd{\@makechapterhead}{50\p@}{-20pt}{}{}
%\patchcmd{\@makeschapterhead}{50\p@}{-20pt}{}{}

\patchcmd{\@makechapterhead}{50\p@}{-22pt}{}{}
\patchcmd{\@makeschapterhead}{50\p@}{-22pt}{}{}
\makeatother
\usepackage[bookmarks, colorlinks=false, pdfborder={0 0 0}, pdftitle={<pdf title here>}, pdfauthor={<author's name here>}, pdfsubject={<subject here>}, pdfkeywords={<keywords here>}]{hyperref} %for creating links in the pdf version and other additional pdf attributes, no effect on the printed document
%\usepackage[final]{pdfpages} %for embedding another pdf, remove if not required

\begin{document}
\renewcommand\bibname{REFERENCES} %Renames "Bibliography" to "References" on ref 
%\newcommand{\chaptersize}{\fontsize{14}\selectfont}
\chapterfont{\centering}
%include other pages
\input{./title.tex}
\input{./certificate.tex}
\input{./Declaration.tex}
\input{./Acknow.tex}

\pagenumbering{roman} %numbering before main content starts


\tableofcontents
\pagebreak
\input{./abstract.tex}
\listoffigures
\listoftables
\include{Abbreviations}

\newpage
\pagenumbering{arabic} %reset numbering to normal for the main content
\input{./Introduction.tex} %objective changed to problem definition
\input{./Literaturesurvey.tex}%literature survey included in this
\input{./SystemDevelopment.tex}
\input{./PerformanceAnalysis.tex}
\input{./Conclusion.tex}
\input{./Ref.tex}
\end{document}

Answer 1

With sectsty:

\documentclass[12pt]{report}
\usepackage{sectsty}
\chapterfont{\large\bfseries}
\begin{document}
\chapter{This is a chapter}
\end{document}