Explaining how a louver motor operates is much easier when you can watch the louver blade move, each step of the way. This project is meant to simplify the operation of the louver motor by visually showing the louver blade movement as 12V power is temporarily applied to each of the 4 electrical coils in sequence. Why does the Louver Motor Matter? The louver motor is often an overlooked component on ductless systems. That is of course, until the unit isn't allowing the air to

This article covers the ten most common locations where refrigerant leaks may be on an air conditioning system. An electronic leak detector is typically used to find the general area of the leak and non-corrosive bubble leak detector is used to pinpoint the leak. In the following pictures, an Accutrak ultrasonic leak detector and Big Blu non-corrosive bubble leak detector are used to search for and find refrigerant leaks. A ultrasonic leak detector (see photo below) locate

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 not have HVAC/R experience and are relying on prior job experiences, a professionally made resume, and the interview process to land the job. As in any field of work, there are certain interview strategies and techniques that will help you get hired. This article covers ten top interview tips when applying for a career in HVAC/R. A successf

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 oil furnace, air handler, or packaged unit. There are multiple reasons why the motor won't start and these are based on the type of unit, controls, and the blower motor type. Problem # 1: Capacitor When an HVAC unit is equipped with a PSC (Permanent Split Capacitor) blower fan, a capacitor is required to both start and run the motor. The cap

In this article, we discuss the accumulator tank, its function, why its used, and its location in the system. The photo below shows the inside of an accumulator tank (left) and an accumulator tank mounted on the side of a rotary compressor (right) . Uses of an Accumulator Tank An accumulator tank is factory installed on the following: Heat pumps as a storage tank because during heating mode there may not be as much refrigerant needed as when in cooling mode. Some outdoor c

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 braze or solder connection. Swaging is a method used on ACR (Air Conditioning, Refrigeration) copper tubing for refrigerant as well as soft copper tubing used for plumbing. Swaging is done to reduce the amount of brazed or soldered joints in a tubing run. In the case of a coupling, two braze joints are needed, whereas with a swage, only one

The Purpose of a Start Capacitor A start capacitor can be found in the electrical compartment of most single speed heat pumps and some outdoor air conditioning units. It can be identified by its cylindrical shape and black plastic body. These are often used in a system design where the unit must operate during low outdoor temperature conditions and/or when there is a non-bleed TXV installed in the refrigerant circuit. A non-bleed TXV does not allow the refrigerant pressures

Basic Characteristics of a Good Instructor "The hardest year of teaching is the one you are currently in." - Ty Branaman Based on their experience, Ty Branaman and Craig Migliaccio believe the following characteristics, strategies, behaviors, and habits make a good instructor. Tip #1: A good instructor cares. People matter to the instructor. Therefore, the instructor care

If a furnace or air conditioning system develops an airflow problem, there are several items to visually inspect. If visual inspection does not locate the issue, proper testing tools are required to determine where the problem is and how severe it is. First visually inspect the air filter to see if it is dirty or clogged. Replace if it is too restrictive or clogged. The back of the evaporator coil could become clogged if there is no air filter or the filter is dirty. The evap

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 to pull outdoor air into the attic from either the side gable vents or from the lower holes in the soffit. The fan then pushes the air out the attic through its penetration hole in the roof. The object is that fresh air (at the same temp as the outside air) is moving through the attic. Otherwise, non-circulating air would remain trapped wit

There are four methods for bending soft copper tubing. Copper tubing can be bent to the correct measurement using a lever type bending tool, a ratcheting type tubing bender, a spring tube bender, or by manually bending the tubing by hand. Step-by-step instructions for tube bending are listed below. Small Lever Type Tube Bender 1. Small Lever Type Tube Bender : This type of tube bending tool is designed to bend soft copper tubing with an OD of ¼”, 5/16”, or 3/8”. The copper

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, or to warm our water, these fuels are constantly around us and as installation and service technicians, it is critical that we be aware of how to safely and accurately pressure test gas lines to test for and prevent potential leaks. In this article, we will be using the IFGC ( International Field Gas Code) 2021 as the reference and discussin

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 run. Before turning the power off to the furnace or opening the doors to the furnace, check the LED status code light (if equipped) for any error codes. On the furnace, there should be a correlating error code list. This will help in the initial diagnosis of the problem. Reason #1: One of the 24v Electrical Safety Switches Inside the Furnace H

This article explains how to troubleshoot a refrigerator or freezer compressor that does not start. There are different components that can be tested to find out what the problem is. To begin troubleshooting, turn the power off to the compressor. If there is a plastic faceplate over the compressor tabs, remove this. There may be multiple different components inside that are mounted onto the 3 compressor tabs. Below are different examples of what may be found inside. Later in

In this HVAC Training Article, I discuss how to perform electrical troubleshooting on an HVAC/R compressor to determine if it is bad. Too many times, compressors are condemned without taking the proper measurements to verify that they are damaged. To help prevent this, I wanted to cover how to check and test various compressors. A multimeter is needed in order to measure electrical resistance at each of the following steps. Before doing any testing on the compressor, make su

A Cad (Cadmium Sulfide) Cell is a photo conductive flame detector that changes its electrical resistance depending on how much light is available at the sensor. This is a common flame detection device used on fuel oil fired burners. The Cad Cell is used in conjunction with an Oil Primary Control mounted to the oil burner. When the Cad Cell is mounted inside the oil burner and the oil burner is off, the location is dark and therefore the resistance reading between the two yell

This article explains the "Top 5 Problems" that can occur on a contactor and how to troubleshoot them! The HVAC Contactor is a device that turns on the outdoor unit compressor and outdoor fan for air conditioners and heat pumps. First, let me briefly explain what the contactor is and how it works. HVAC contactors typically come as single, double, or triple pole. This refers to the amount of poles it can switch on or off. The switching action occurs when powering the lower coi

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 locking port cap. C&D Valve CD3830 Universal Locking Cap Removal Tool with 3 Bits Be Prepared! A Locking Cap Multi-Key can save you a ton of time and frustration. Trust me, if you don’t have the key, you won’t be very happy! More importantly, you don't want to be the tech who is trying to cut a locking cap off with a Sawzall or some other

When installing a new HVAC system, replacing an existing HVAC system, or only replacing one part of the system, there is a sequence of procedures that must be performed for the refrigerant tubing to prepare for refrigerant. When replacing an existing system, start at Procedure 1 . When installing a new system, start at Procedure 2 . Remember, under US federal guidelines, technicians must be EPA 608 certified before handling refrigerants. Procedure 1, Recover or Pump Down: I

Downloadable Wiring Diagrams and the measurement layout are available at the bottom of this page. Instructors are always looking for a low cost, hands-on project, that is safer to teach their students about HVAC Electrical Wiring, Components, Thermostats, Thermostat Wiring, and an Intro to Electrical Troubleshooting! This small electrical training board can be built by each student and it allows each student to get some hands-on training. The teacher can provide the step by s