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Home » Authors » John Tomczyk

Articles by John Tomczyk

Compressor Troubleshooting

Troubleshooting Worn Rings and Leaky Valves

Technicians must perform a complete service checklist to find the underlying problem
John Tomczyk
May 16, 2023
Learning how to troubleshoot a system that is experiencing leaky valves or worn rings can be challenging, so technicians need to take careful measurements in order to isolate the problem.
Read More
Technicians Servicing Refrigeration Equipment

What Causes High Compressor Discharge Temperatures?

Technicians must take measurements of a system in order to determine the problem
John Tomczyk
April 12, 2023
There are several reasons why a refrigeration or air conditioning system may have high compressor discharge temperatures. That’s why technicians must carefully measure the system’s temperatures and pressures to determine the problem.
Read More
Refrigertation Checklist

Checklists Can Help Determine What Is Causing the Problem in a Refrigeration System

Confusing High-Side Temperatures
John Tomczyk
March 22, 2023
There are several reasons why the compressor discharge temperature of a refrigeration system can be high when the condensing temperature is not, and a checklist can help a technician figure out the root problem.
Read More
Relay Components

Troubleshooting Potential Relays

A malfunctioning relay can damage the compressor, so techs must understand the warning signs
John Tomczyk
February 15, 2023
If a potential relay is malfunctioning, the compressor motor is in danger of not starting, stalling, locking rotor, or even burning out. That is why technicians should understand how to troubleshoot potential relays.
Read More
Professor John Tomczyk

The Definitive Guide to Temperature Glide, Part 2

Always consult the P/T chart when calculating superheat and subcooling for refrigerant blends
John Tomczyk
January 20, 2023
Service technicians need to be careful when reading the pressure/temperature chart because if they choose the wrong values, they will make mistakes diagnosing the system.
Read More
Refrigerant Technician

The Definitive Guide to Temperature Glide, Part 1

Technicians must understand how to calculate temperature glide for refrigerant blends
John Tomczyk
November 30, 2022
The HVACR industry will soon be using low-GWP refrigerant blends, some of which have a temperature glide when evaporating and condensing. As these refrigerant blends change phase, there’s a change in their composition, which technicians must be able to calculate while in the field.
Read More
Refrigeration Troubleshooting

Creating the Ultimate Refrigeration Troubleshooting Checklist

Being organized can help technicians quickly solve tough problems in the field
John Tomczyk
November 2, 2022
In addition to using proper tools and test instruments, technicians should use a checklist to help them troubleshoot refrigeration and air conditioning systems in the field.
Read More
Refrigeration Evaporator.

Proper Superheat Can Protect Compressor From Damage

Technicians should make sure that liquid refrigerant is not entering the compressor
John Tomczyk
September 28, 2022
One of the worst enemies of a compressor is liquid refrigerant, so technicians should make sure the refrigeration system has proper superheat in order to protect the compressor from damage that can occur from flooding or slugging.
Read More
Professor-JohnTomczyk1.jpg

Reasons Why TXVs Underfeed Refrigerant

A refrigerant undercharge may be due to TXV restriction
John Tomczyk
August 30, 2022
Technicians need to make sure that the TXV is not underfeeding refrigerant to the refrigeration or air conditioning system due to a restriction, which can be caused by a number of factors.
Read More
TXV.

Reasons Why TXVs Overfeed Refrigerant

Proper TXV settings will keep refrigeration and air conditioning systems operating efficiently
John Tomczyk
July 27, 2022
Making sure the TXV is metering the right amount of refrigerant into the evaporator and is not overfeeding the coil is one way technicians can help their customers’ refrigeration and air conditioning systems operate safely and more efficiently.
Read More
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