There are three distinct types of muscles: skeletal muscles, cardiac or heart muscles, and smooth (non-striated) muscles.
HVAC technicians are responsible for the installation, maintenance and repair of heating, ventilation and air conditioning (HVAC) systems. As an HVAC technician, your job duties may include inspecting existing systems and making recommendations intended to improve the efficiency and/or safety of that system's performance. HVAC-R techs may also work on refrigeration systems.
totalpics/iStock/Getty Images. Heating, ventilation and air conditioning technicians repair, maintain, install and remove heating, cooling and ventilation systems in residential and commercial settings. Some HVAC technicians get additional training and certification to work on refrigeration systems.The Bureau of Labor Statistics says that those wishing to become HVAC technicians generally must become licensed to practice, but getting certification can improve employment opportunities.owever, entering a certificate or degree program can provide the education that an aspiring HVAC technician needs to pass the certification exam. Those who complete a formal degree program can also take the exam with only two years of work experience, as opposed to three.