Servicing Refrigeration Systems and Components

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Electrical/General Safety

Heat Transfer

HVAC Tools/Components


Review "Normal" High Side Conditions

This topic describes normal high side conditions in systems and how to achieve them.

Review "Normal" Low Side Conditions

This topic describes normal low side conditions in systems and how to achieve them.

Temperature Split

The temperature split test is a quick and easy way of checking an HVAC system airflow and capacity.

Evaporator Temperature Difference

In this topic, we discuss how to measure temperature differences in an evaporator.

Refrigerant Restriction

Teaches you how to diagnose liquid line restriction, and the steps to take to remedy the issue.

Inefficient Compressor

In this topic, we explain how to diagnose and troubleshoot an inefficient compressor, and determine when it is beyond repair and requires replacement.

Inadequate Evaporative Airflow

This topic explains how to check for adequate airflow across the evaporator coil and how to fix any issues.


This topic details how to use non-condensables, most commonly air and nitrogen, in refrigeration systems.

Refrigerant Overcharge

This topic explains how to fix a system with overcharged refrigerant.

Low Ambient Control

This topic covers how to service head pressure control valves and adjust system conditions to match the needs of the customer.

Thermal Expansion Valve Flooding

TXV's and other metering devices can flood. Knowing how to deal with this frustrating issue can save you many headaches on the job.

Condenser Operation

This topic explores the operation of a condenser, and how to fix common issues associated with it.

Frequently Asked Questions

How Is the online course set up?

When building the course, our goal was to make online HVAC training fun, engaging, and exciting! With that goal in mind, we have put a tremendous amount of multimedia material into our courses. As a student, you will never just be reading or listening to text- this is not a textbook!​ Every single part of our courses is full of compelling graphics, informative animations, and real-life images from HVAC systems. After each lesson- and within many lessons- you will be asked to answer HVAC technician questions or do HVAC system calculations focused on what you just learned. These HVAC system exercises make learning a lot more interactive and fun.

Will you help me get hired after the course?

Once you complete the online HVAC training, you will have the option to join our talent network. We have partnered with leading HVAC companies, and they are all hiring right now! Companies will look for new hands from this talent pool since you have proven your ability through training simulations and testing. To join our talent pool, take the HVAC assessment on our website.

How much do the online courses cost?

Nothing! Our online HVAC training is entirely free, and we have made it as simple as possible. We took out all the filler, which can cause similar programs to take up to a year, and worked with hiring managers to teach you the skills that you need to know to start your career in HVAC.

How do the simulations work?

We developed the HVAC training simulations based on real-world scenarios that you will encounter as an HVAC technician. These simulations allow us to test you on the information you just learned, and they teach you how to apply the knowledge to practical tasks.

Do I need a computer for the online training courses?

To take our free online HVAC course, you will need a phone, tablet, or computer with an internet connection. A lot of our graduates took classes while they were on the job site or in between jobs. The HVAC course is super convenient and always accessible.

Is there a textbook for the online training?

No textbooks here! We wanted to design a free, online HVAC course that wasn't boring. All of our courses use animations, simulations, and quizzes to teach you the skills you will need to become an HVAC tech.

Do hiring managers like online courses like this?

Absolutely. We designed these courses with hiring managers from large HVAC companies to be sure that everything in the course is essential and approved by them. Also, hiring managers love simulations since it gives them a better understanding of how you apply the knowledge you learned in the course. That gives you an advantage over anyone who has just been studying a textbook.

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