Articles and Tips
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Quick Tips
Using the Total Superheat Charging Method for HVAC Units!
The Total Superheat method step by step for fixed orifice systems. See also Target Superheat.
Quick Tips
Why Can't You Just Measure Pressures to Check a Refrigerant Charge?
Why pressure alone does not tell you whether the charge is correct.
Quick Tips
Checking the Charge of a Mini-Split Unit!
How checking the charge on an inverter mini split differs from a single speed system.
Quick Tips
10 Reasons Why a Mini-Split Ductless Flare May Leak Refrigerant!
Ten things that cause a flare connection to leak on a ductless mini split.
Quick Tips
How NOT to Check the Refrigerant Charge!
The common shortcuts that produce a wrong charge, and what to do instead. See Charging Procedures.
Quick Tips
Charging a System in a Dry Climate? Consider a TXV and Accumulator!
Why a dry climate changes the charging picture, and where a TXV and accumulator help.
Quick Tips
R-22 and R-410A Operating Pressures, Charging, and Recovery Setup!
Operating pressures for R-22 and R-410A, plus the charging and recovery setup for each. See the P/T Chart.
Quick Tips
Checking the Charge of Air Conditioners Without Measuring Pressure!
How to assess a refrigerant charge without connecting gauges, and when that is appropriate.
Quick Tips
40 Vacuum Tips for HVACR Technicians! Avoid Frustration!
Forty practical tips for pulling a proper vacuum without the frustration.
Quick Tips
Is There an Easy Way to Tell if a Mini-Split Ductless Unit is Low on Refrigerant? (Quick Tip)
A quick tip for spotting a low charge on a ductless mini split.
Quick Tips
Clogged Liquid Line Filter Drier?
How to tell when a liquid line filter drier is restricted, and what it does to system readings.
Quick Tips
Troubleshooting an HVAC Control Board? How?
How to approach a control board before condemning it.
Quick Tips
What Components are in a Forced Air Gas Furnace? What do they Do?
Every major component inside a forced air gas furnace and the job each one does.
Quick Tips
Ductless Mini-Split Step-by-Step Installation
A full step by step ductless mini split installation. See also The Mini Split Book.
Quick Tips
The Benefits of Using an Ultrasonic Leak Detector to Find Refrigerant Leaks!
Why an ultrasonic leak detector finds leaks that other methods miss.
Quick Tips
Finding a Low Voltage Short Quickly, Step by Step!
A step by step method for isolating a short in a 24 volt control circuit.
Quick Tips
20 Causes of Low Indoor Airflow on Ducted HVAC Units!
Twenty things that restrict indoor airflow on a ducted system, and how to check each.
Quick Tips
Gas Furnace Electrical Safety Switch Testing!
Testing the electrical safety switches on a gas furnace.
Quick Tips
How to Find Common, Start, and Run on a PSC Compressor Motor!
Identifying the common, start and run terminals on a PSC compressor using resistance readings.
Quick Tips
Top 10 Gas Water Heater Pilot Light Problems! When It Won't Stay Lit!
Ten reasons a gas water heater pilot light will not stay lit.
Quick Tips
Adjusting the Furnace/AC Airflow Speed on a 120v PSC Blower Motor!
Changing blower speed taps on a 120v PSC motor in a furnace or air handler.
Quick Tips
Adjusting the Airflow Speed on ECM Blower Fan Motors! (Variable & Multi-Speed Types)
How to change airflow speed on variable and multi-speed ECM blower motors.
Quick Tips
TXV Bulb Mounting Position and External Equalization!
Where the TXV sensing bulb should be mounted, and how external equalization works.
Classroom Projects
HVAC Electrical Training Board For Wiring, Components, Wiring Diagrams, Troubleshooting
A low cost hands-on training board that teaches thermostat wiring, components, diagram reading and electrical troubleshooting. Full build guide on ...
Quick Tips
When Installing or Replacing an Air Conditioner, Use These Procedures for the Refrigerant Tubing!
The refrigerant tubing procedures to follow on an air conditioner installation or changeout.
Quick Tips
Don't Get Locked Out! Locking Port Cap Quick Tip!
A quick tip on locking refrigerant port caps.
Quick Tips
TOP 5 HVAC CONTACTOR Troubleshooting Problems!
The five contactor faults that come up most often, and how to confirm each one.
Quick Tips
Troubleshooting a Cad Cell Flame Detector for an Oil Burner!
How the cad cell works on an oil burner and how to troubleshoot it.
Quick Tips
Testing if an HVACR Compressor is Shorted to Ground, Open, or the Thermal Overload is Tripped!
How to tell a compressor that is shorted to ground from one that is open or simply on thermal overload.
Quick Tips
Fridge or Freezer Compressor Not Starting? Test Start Relay, Overload, Capacitor, PTC Thermistor
Testing the start relay, overload, capacitor and PTC thermistor when a refrigerator or freezer compressor will not start.
Quick Tips
6 Reasons Why a Furnace Blower Fan Motor Won't Shut Off!
Six reasons a furnace blower keeps running, and how to isolate which one it is.
Quick Tips
Pressure Testing Gas Lines for Leaks! Natural Gas and Propane (LP)
How to pressure test natural gas and propane lines for leaks.
Quick Tips
Copper Tube Bending Tools and Methods
The tools and techniques used to bend copper tube without kinking it.
Quick Tips
ATTIC FANS! Troubleshooting Common Problems!
Common attic fan faults and how to track them down.
Quick Tips
Finding an Airflow Problem using Static Pressure Measurements!
How static pressure readings point to where an airflow restriction actually is.
Quick Tips
Tips For New HVACR Instructors with Ty and Craig!
Craig and Ty Branaman share what works in the classroom, in the shop and in the field for instructors new to teaching HVACR.
Quick Tips
Why a Start Capacitor Fails and Testing!
What causes a start capacitor to fail, and how to test one correctly.
Quick Tips
Copper Tube Swaging and Deburring Tools!
The tools used for swaging and deburring copper tube, and how to get a clean joint.
Quick Tips
Suction Line Accumulator Tank Function, Location, & Purpose
What the accumulator tank does, why it is used, and where it sits in the system.
Quick Tips
10 Reasons a Blower Fan Won't Start in a Furnace, AC or Heat Pump
The ten most common reasons a blower fan does not turn on. A blower motor may be installed in a forced air gas or oil furnace, air handler, or pack...
Quick Tips
Top Ten Interview Tips to Land that HVAC/R Job!
Good training and experience matter, but the interview process is what lands the job. Ten tips for presenting yourself well, whether or not you alr...
Quick Tips
Where To Find R-22 & R-410A Leaks on AC Units! Top 10 Spots!
This article covers the ten most common locations where a refrigerant leak may be on an air conditioning system. An electronic leak detector is typ...
Articles
Top 10 Gas Furnace Package Unit Problems!
Common gas furnace package unit failures, starting with checking for power at the control board LED.
Articles
Carbon Monoxide Alarm vs Low Level CO Monitor
Compares standard CO alarms with low level CO monitors, and the health effects of low level carbon monoxide exposure.
Articles
Measuring Airflow in CFM Using the TrueFlow Grid
Airflow is often skipped due to a lack of easy methods and tool accuracy limits. A review of the options and how the TrueFlow Grid measures CFM.
Articles
Measuring the Static Pressure Drop Across an Evaporator Coil to See if it is Clogged!
Static pressure readings reveal how restricted a hidden evaporator coil has become.
Articles
5 Methods to Determine if The Indoor Air Conditioning Coil is Clogged with Dust!
Dust buildup from missing or poorly fitted filters reduces airflow and efficiency. Five ways to detect a clogged indoor coil.
Classroom Projects
Seeing the TXV Metering Device Operate Using A Water Stream!
A classroom project that uses a water stream to show how a TXV or piston changes liquid flow, making metering device operation visible rather than ...
Classroom Projects
How to Read a Tape Measure in Inches and Fractions!
A training method using marked wood pieces and fraction sheets to teach apprentices to read a tape measure. Covers the 1/2, 1/4, 1/8 and 1/16 inch ...
Articles
The HVAC Interview: Preparing and Dressing for Success
Landing a job in HVAC is unique because every employer has a different philosophy on professionalism. The goal is to look capable and ready to work...
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