HVACR Articles

Jul 248 min read

5 Methods to Determine if The Indoor Air Conditioning Coil is Clogged with Dust!

When servicing an air conditioner or heat pump, we often notice a low airflow problem which needs to be fixed. If there is no indoor air...

2,989 views3 comments

Jul 35 min read

Measuring the Static Pressure Drop Across an Evaporator Coil to See if it is Clogged!

If you suspect that an evaporator coil is clogged with dust but cannot visually see it, such as when you can't directly inspect on a...

2,676 views2 comments

Dec 13, 20235 min read

Measuring Airflow in CFM Using the TrueFlow Grid

Measuring airflow is one of the most commonly missed or ignored topics in HVAC when commissioning or diagnosing problems in systems. I...

2,590 views1 comment

Nov 29, 20234 min read

Carbon Monoxide Alarm vs Low Level CO Monitor

Today most people are aware of the invisible, odorless, poisonous gas of Carbon Monoxide or CO for short. Now we know that even low...

983 views0 comments

Nov 1, 20239 min read

Top 10 Gas Furnace Package Unit Problems!

Problem #1: No Power to the Package Unit On all HVAC systems, power is critical to operation, and a package unit is no different. There...

2,873 views3 comments

Sep 29, 20227 min read

Where To Find R-22 & R410A Leaks on AC Units! Top 10 Spots!

This article covers the ten most common locations where refrigerant leaks may be on an air conditioning system. An electronic leak...

8,671 views2 comments

Sep 7, 20227 min read

Top Ten Interview Tips to Land that HVAC/R Job!

It is certainly important to have good training and/or experience in the field prior to applying for an HVAC/R position. However, some do...

1,987 views1 comment

Jul 27, 20228 min read

10 Reasons a Blower Fan Won't Start in a Furnace, AC or Heat Pump

This article covers the 10 most common reasons the blower fan does not turn on! A blower motor may be installed in a forced air gas or...

61,452 views10 comments

Jul 20, 20224 min read

Suction Line Accumulator Tank Function, Location, & Purpose

In this article, we discuss the accumulator tank, its function, why its used, and its location in the system. The photo below shows the...

6,992 views0 comments

Jul 13, 20225 min read

Copper Tube Swaging and Deburring Tools!

Swaging tools are used to expand the end of a copper tube to accept the next section of tubing. This is done prior to making a permanent...

5,476 views1 comment

Jul 6, 20225 min read

Why a Start Capacitor Fails and Testing!

The Purpose of a Start Capacitor A start capacitor can be found in the electrical compartment of most single speed heat pumps and some...

17,237 views0 comments

Jun 28, 20227 min read

Tips For New HVACR Instructors with Ty and Craig!

Basic Characteristics of a Good Instructor "The hardest year of teaching is the one you are currently in." -Ty Branaman Based on their...

1,279 views1 comment

Jun 21, 20228 min read

Finding an Airflow Problem using Static Pressure Measurements!

If a furnace or air conditioning system develops an airflow problem, there are several items to visually inspect. If visual inspection...

10,840 views3 comments

Jun 14, 20226 min read

ATTIC FANS! Troubleshooting Common Problems!

An attic fan is used to lower the temperature within the building shell between the roof structure and the living space. The fan's job is...

17,725 views4 comments

Jun 8, 20225 min read

Copper Tube Bending Tools and Methods

There are four methods for bending soft copper tubing. Copper tubing can be bent to the correct measurement using a lever type bending...

10,784 views0 comments

May 9, 20227 min read

Pressure Testing Gas Lines for Leaks! Natural Gas and Propane (LP)

Fuel gases such as Propane or Natural Gas are a regular part of everyday life for many. Whether it is used to heat a home, cook a meal,...

50,302 views2 comments

May 3, 20225 min read

6 Reasons Why a Furnace Blower Fan Motor Won’t Shut Off!

On a natural gas or propane furnace, there are typically 6 main reasons why a blower fan motor may not shut off and just continues to...

41,059 views4 comments

Apr 18, 20229 min read

Fridge or Freezer Compressor Not Starting? Test Start Relay, Overload, Capacitor, PTC Thermistor

This article explains how to troubleshoot a refrigerator or freezer compressor that does not start. There are different components that...

28,773 views1 comment

Apr 11, 20228 min read

Testing if an HVACR Compressor is Shorted to Ground, Open, or the Thermal Overload is Tripped!

In this HVAC Training Article, I discuss how to perform electrical troubleshooting on an HVAC/R compressor to determine if it is bad. Too...

84,077 views3 comments

Dec 15, 20213 min read

Troubleshooting a Cad Cell Flame Detector for an Oil Burner!

A Cad (Cadmium Sulfide) Cell is a photo conductive flame detector that changes its electrical resistance depending on how much light is...

18,929 views0 comments

Jun 30, 20216 min read

TOP 5 HVAC CONTACTOR Troubleshooting Problems!

This article explains the "Top 5 Problems" that can occur on a contactor and how to troubleshoot them! The HVAC Contactor is a device...

36,867 views1 comment

Jun 22, 20211 min read

Don't Get Locked Out! Locking Port Cap Quick Tip!

Just because your company only uses one type of port cap doesn’t mean you won’t be called to service a system with another manufacturer’s...

3,499 views3 comments

Jun 9, 20216 min read

When Installing or Replacing an Air Conditioner, Use These Procedures for the Refrigerant Tubing!

When installing a new HVAC system, replacing an existing HVAC system, or only replacing one part of the system, there is a sequence of...

9,624 views1 comment

Jun 1, 20218 min read

HVAC Electrical Training Board For Wiring, Components, Wiring Diagrams, Troubleshooting

Downloadable Wiring Diagrams and the measurement layout are available at the bottom of this page. Instructors are always looking for a...

25,482 views5 comments

May 26, 20213 min read

TXV Bulb Mounting Position and External Equalization!

The question we are looking to answer is, should we install the TXV bulb before (upstream) or after (downstream of) the external...

22,844 views2 comments

May 19, 20217 min read

Adjusting the Airflow Speed on ECM Blower Fan Motors! (Variable & Multi-Speed Types)

In this HVAC training article, we will be discussing how to adjust the fan speeds on an indoor ECM variable speed blower motor and an ECM...

100,018 views9 comments

May 12, 20214 min read

Adjusting the Furnace/AC Airflow Speed on a 120v PSC Blower Motor!

In this HVAC training article, we will be discussing how to adjust the fan speeds on an indoor PSC blower motor in furnace and air...

11,759 views1 comment

May 6, 20218 min read

Top 10 Gas Water Heater Pilot Light Problems! When It Won’t Stay Lit!

This article explains how the thermocouple, gas valve solenoid, and pilot flame work on a water heater. I will be discussing 10 problems...

14,247 views2 comments

Apr 28, 20214 min read

How to Find Common, Start, and Run on a PSC Compressor Motor!

In this HVACR Training article, we are using electrical resistance measurements on the PSC compressor terminals in order to determine...

45,642 views4 comments

Apr 21, 20215 min read

Gas Furnace Electrical Safety Switch Testing!

In this article, we will be discussing methods to test the safety switches in a gas furnace using a multimeter. These switches include...

10,248 views0 comments

Apr 14, 20217 min read

20 Causes of Low Indoor Airflow on Ducted HVAC Units!

In this HVAC training article, I discuss 20 AIRFLOW Problems that you may find on ducted gas furnaces, air conditioners, heat pumps, air...

5,754 views0 comments

Apr 8, 20218 min read

Finding a Low Voltage Short Quickly, Step by Step!

In the world of HVAC, low voltage shorts are a common occurrence on a service call. Low voltage shorts occur when an electrical circuit...

61,770 views6 comments

Feb 3, 20215 min read

The Benefits of Using an Ultrasonic Leak Detector to Find Refrigerant Leaks!

A refrigerant leak may be easy to find when the leak is a large one but when the leak is small, finding it can be tedious and time...

81,361 views0 comments

Nov 25, 202015 min read

Ductless Mini-Split Step-by-Step Installation

In this step-by-step installation, we will be covering the full installation of a ductless Mini-Split heat pump system. This system...

17,332 views2 comments

Oct 21, 20208 min read

What Components are in a Forced Air Gas Furnace? What do they Do?

In order to troubleshoot a gas furnace, the technician must have a thorough knowledge of each component that could be in the unit....

10,601 views0 comments

Sep 23, 20205 min read

Troubleshooting an HVAC Control Board? How?

Diagnosing if a control board is bad on a furnace, air conditioner, or heat pump may seem difficult but here are some simple tips and...

34,694 views7 comments

Aug 19, 20204 min read

Clogged Liquid Line Filter Drier?

How can you tell if you have a clogged liquid line filter drier? If there is a noticeable temperature drop from one side of the filter...

37,228 views1 comment

Aug 6, 20201 min read

Is There an Easy Way to Tell if a Mini-Split Ductless Unit is Low on Refrigerant? (Quick Tip)

Is there an easy way to tell if a mini-split ductless unit is low on refrigerant? Yes, if the Delta T is low and the system continues to...

15,853 views1 comment

Jul 22, 202010 min read

40 Vacuum Tips for HVACR Technicians! Avoid Frustration!

I put this list together to make sure that HVACR technicians don’t have to undergo the same frustrations, loss of time, and expenses that...

24,748 views2 comments

Jul 16, 20208 min read

Checking the Charge of Air Conditioners Without Measuring Pressure!

Can you check the charge on a system without checking pressure? Sure, remember that the only reason we check pressure is to convert it to...

12,240 views7 comments

Jun 24, 20207 min read

R-22 and R-410A Operating Pressures, Charging, and Recovery Setup!

In this article, we will discuss an HVAC unit’s refrigerant pressure on both the high side and the low-pressure side while the system...

349,075 views13 comments

Jun 11, 20206 min read

Charging a System in a Dry Climate? Consider a TXV and Accumulator!

In a dry climate, certain considerations must be taken prior to installing or servicing air conditioning systems. A TXV metering device...

4,861 views2 comments

May 28, 20208 min read

How NOT to Check the Refrigerant Charge!

There are many ways that technicians have tried to get around actually checking the charge of air conditioners and heat pumps with...

6,574 views2 comments

May 20, 20206 min read

10 Reasons Why a Mini-Split Ductless Flare May Leak Refrigerant!

On a mini-split ductless system, two copper tubes are needed to transport the refrigerant. These copper tubes are referred to as the line...

34,711 views1 comment

May 6, 202011 min read

Checking the Charge of a Mini-Split Unit!

A question that I get asked frequently is “Can I check the charge of a mini-split ductless unit with superheat and subcooling the same...

146,809 views24 comments

Apr 22, 20209 min read

Why Can’t You Just Measure Pressures to Check a Refrigerant Charge?

Most technicians in the HVAC field know the normal range of operation for the low-pressure side of an air conditioning system. This tends...

102,617 views10 comments

Apr 16, 202010 min read

Using the Total Superheat Charging Method for HVAC Units!

In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to...

60,596 views3 comments

Apr 8, 20207 min read

The HVAC Subcooling Charging Method, Explained!

In this article, we will define subcooling, calculate subcooling, explain how to use subcooling to check the refrigerant charge, and show...

149,380 views1 comment

Mar 31, 20206 min read

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