How to trouble shoot a system

[US Iceman]

Having just read a post by one of the other Moderators of this forum I noticed a common problem occuring, which he also mentioned.

People come onto the RE forums and asking for help is great. This is a good resource for others in our industry to use and exchange views.

The common problem which seems to occur a lot is; someone will ask a question, without providing sufficient information for the moderators or others to fully understand your questions.

In order to fully realize the nature of the problem we usually ask many questions. These almost always are related to the operating conditions of the system.

Attached is basic diagram to illustrate why we ask these questions. The diagram is for a simple refrigeration system. In this diagram you will see four different areas where pressures and temperatures are shown.

These basic points of operation provide the condition of the refrigerant on each side of the component, i.e., compressor, condenser, expansion device, and evaporator.

These data points indicate what the refrigerant is doing at each location and helps to show what may be normal or causing the problem.

This does not take expensive or fancy tools; only a gauge set and a thermometer.

With this information and knowing which refrigerant is being used in the system, you can determine a lot of the problems as you gain experience. One of the benefits of this is; you become more familiar with the state of the refrigerant by knowing the pressure and temperature at each location.

All normally used refrigerants are similar. At some operating condition the refrigerant can be 100% liquid, 100% gas, gas & liquid, or superheated or subcooled.

Only gases can be superheated, and only liquid can be subcooled.

By also having the pressures at each component (in & out) you also develop some experience in reasonable pressure losses between the components.

Try this out and think about it. Ask questions. I think you will find as you get used to doing this, your job gets a little easier and less frustrating.

One last comment for consideration. Some of the best tools for trouble shooting refrigeration systems are:

a) eyes
b) ears
c) touch
d) smell
e) feet

All of the above?

Which ones do you use?