HVAC Tech Tips

Our Tech Tips come straight to your inbox once a month. However, if you can't find the tip you're looking for in your email, try searching for it here. If you need any more assistance please feel free to reach out to our HVAC Technical Support Team 330-475-8230.

Commissioning    Maintenance    Service and Diagnosis   Tool    Warranty

Static Pressure Testing (2021)

Being able to calculate the airflow in a duct system is critical, whether you are performing service or designing a new system. When we refer to static...

Generator Start Up

Generator sales are up due to the storms and while the installation is fairly straight forward, the start up is sometimes neglected. Here we discuss how to properly start up...

Why Do a Start Up

When a new piece of equipment is installed, a start- up or "commissioning" MUST be done. Why is that? When the equipment is initially started...

Clocking a Gas Meter

There are times that you may need to clock a gas meter. This is required on a start-up of a new furnace or to verify the input of an existing application. This will verify the...

The Idea Behind Crankcase Heaters

Why do we see crank case heaters installed? Is it just an extra part to wear out or does it actually help the system? Crankcase heaters are there for a reason...

Static Pressure Testing (2019)

Being able to calculate the airflow in a duct system is critical, whether you are performing service or designing a new system. When we refer to static...

Combustion Air

All fuel-burning appliances require oxygen to burn safe, cleanly and efficiently. In this case, safe means without excess CO (Carbon Monoxide). A safe...

Evacuation Procedures

Well, the warm weather is here, and with that comes an increase in AC installs. I wanted to take a moment to discuss the right way to...

Ice in the Lines

Did you know that ice can form in a vacuum even when it’s warm out? So what causes this (water freezing under vacuum) and...

14 SEER Heat Pump System

We’ve had numerous questions over the last few weeks where a heating contractor is replacing a heat pump system for a homeowner and they want...

Choosing the Proper Mitsubishi Electric System

I have received several questions regarding which Mitsubishi system would be appropriate for their application. Since Mitsubishi systems come in a wide range of...

Codes and Changes

You may have noticed a few recent changes when placing orders for HVAC related material with Famous Supply. The Ohio Revised Codes have recently changed...

Cold Weather is Coming!

Sorry to break it to you, but cold weather is coming. Before you start throwing tomatoes my way, this is only some advice to help...

Heat Pump Basics

One of the often-overlooked aspects of installing a heat pump is the location. As a heat pump runs in heating mode it tends to build...

Mitsubishi Electric Updates and Applications

Hello Everyone! As the HVAC industry changes so does the Mitsubishi Electric line- up. I would like to take a moment to introduce some of...

POE vs. Mineral Oil

As many of you have already noticed, all Copeland, R22 compressors are now being shipped with POE oil instead of the standard mineral oil. This...

Proper Start Up

The summer is in full swing and I’m sure you are staying busy. With that being said, please take time to do a proper start...

Sizing Equipment

We often get asked, “What size furnace/AC do I need?” The answer is not as simple as just knowing the square footage. There is a...

Why We Use Dry Nitrogen

We are gearing up for the air conditioning start up season and you know what that means: more AC installations. As the number of installs...

Thermistor

As our industry changes and becomes more reliant on circuit boards to control the functions of our equipment, the way temperature...

Why do a load Calculation?

When sizing a furnace or AC, a load calculation must be done. The most common method is the Manual J. While we are not going ....

The Side Effect of Higher Efficiency Air Conditioning Units

Over the past few years, the government has mandated increased minimum efficiencies for about everything, including heating and....

Multizone Breeze33 Charging

When a multizone Breeze33 (generation 1) system is installed, sometimes additional refrigerant must be added...

Ordering the Correct Mitsubishi Part

Nothing is more frustrating to you and your customer than to order a replacement part and receive the wrong part...

Replacement Solution for Aerosys Aeropaks

Aeropaks were a completely self-contained thru-the-wall heating and cooling system for apartments and condos...

Understanding Mini Split Wire Sizes

Lately, we have received numerous inquiries regarding wire sizes for connecting indoor units and line sets in Mitsubishi and Breeze33...

Lineset Installation Requirements

JMF EZ-Pull is the recognized industry-leader for premium quality hard shell lineset insulation. To ensure the installation of linesets with the EZ-Pull is performed correctly, please adhere to these required industry installation practices....

How To Measure Subcooling

In most new high efficiency systems, a TXV is utilized as the metering device. That means superheat remains constant through its run cycle...

Safeties, Safeties, and More Safeties

In modern furnaces you may have noticed a lot of safeties. I’ve heard numerous times "boy, these new furnaces are too complicated". Well, there is good...

Testing Capacitors

Testing a run capacitor should be part of your annual maintenance. When testing a run capacitor many techs pull the leads off...

Diagnosing a Smart Valve, First Generation

First generation smart valves act as ignition controls and gas valves. There are internal and external safeties that can prevent the valve from working properly...

Filter Driers and When to Replace Them

When an air conditioner or refrigeration unit is installed a Filter Drier is needed. That Filter Drier stays in the system as long as the...

Filters

There are many misconceptions when it comes to properly sizing a filter. Many installation and service technicians believe that a filter should be sized based...

How to Test a Pressure Switch (2017)

To test a pressure switch, you must first have a compound pressure gauge (digital or analog). Install a plastic tee for both the positive and...

How to Test a Pressure Switch (2013)

To test a pressure switch you must first have a compound pressure gauge (digital or analog). Tee in a plastic tee for both the positive...

Importance of a Filter Drier

Hello all! For this Supply Chain our Technical Tip is straight from Allied Air regarding the use of a filter drier. Using the correct drier...

Properly Evacuating ACs & Heat Pumps

Warm weather is fast approaching, and with that comes an increase in air conditioner installs. This brings up an important topic: correctly evacuating a system...

Specifying a Generator for Use

With cold weather upon us now there will be time when customers will lose power to their homes and will try to operate their furnaces...

Static Pressure

Whether performing an installation in a new construction home or a system change-out on a 50 year old home, knowing the static pressure on your...

Understanding Mitsubishi Wire Sizes

Recently I have been receiving a lot of questions regarding the wire sizes that connect to the indoor units and line set sizes on Mitsubishi...

What is Draft?

Very often you may be asked to check or verify draft. So what exactly is draft and what does it do? Draft is the chimney’s...

Why Use a Start Assist Device On Your Compressor

Many times we receive questions as to why someone would want to install a start capacitor (5-2-1). There are several reasons why this would be...

Heat Exchanger Testing

The first rule for checking a heat exchanger is to always follow the manufacturer’s directions for testing heat exchangers. Another good source of information...

Generator Maintenance

Generators require maintenance every year. Having it maintained can ensure a long life and problem free operation. Generators are designed to run...

Flood Damaged Equipment

Every so often we are asked what to do when flooding occurs in regards to equipment. Here is what our manufacturers have to say...

How To Measure Subcooling

In most new high efficiency systems, a TXV is utilized as the metering device. That means superheat remains constant through its run cycle...

Problematic Thru-the-wall unit?

It’s a common story, an older thru-the-wall unit needs replaced as replacement parts have become obsolete....

Troubleshooting your AC or Ductless System

Every system should have a basis of design. What I mean by that is when....

Resideo

We’ve put together this downloadable quick reference guide of Resideo...

Breaking News for New Furnace Installations

Starting December 1st, Cellular Core PVC will no longer be approved for use on new installations...

Power spikes

Did you know that power quality and reliability issues cost the U.S. economy roughly...

Flooded Equipment

Every so often we are asked what to do when flooding occurs in regards to equipment. Here is what our manufacturers have to say...

Why Use an Economizer?

Economizers are incorporated into most rooftop AC units and for good reason! They increase AC efficiency...

Mitsubishi “Wait” Message

A common issue we see is the Mitsubishi MHK2 thermostat showing “Wait” on the screen. Unfortunately, this often leads to replacing the thermostat or control board. More often than not, the problem is a communication fault and not a “unit” fault...

Properly Sizing A Filter

There are many misconceptions when it comes to properly sizing a filter. Many installation and service technicians believe that a filter should be sized based on a “rule of thumb”. The truth...

Measuring Ohms & Continuity

We often confuse the terminology Ohms and continuity. The two are not the same! An Ohmmeter is used to measure the resistance to electrical flow between...

How to Test a Pressure Switch

To test a pressure switch you must first have a compound pressure gauge (digital or analog). Install a plastic tee for both the positive and negative...

FER is Changing in 2019

In 2014, the US Department of Energy established the first national efficiency standards for furnace fans. FER specifies a maximum fan energy rating that varies based on the airflow provided by...

How Safe is the Home You're Entering?

Do you know how safe the home you're entering is and how safe it is when you leave? What exactly am I talking about? Carbon monoxide...

Air Conditioner Terminology

Hello all! It seems that the air conditioning season is upon us (finally)! As such, I figured this would be a good time to review...

Air in Hydronics

When working with a hydronic system the biggest enemy is air. An air bubble can reduce the amount of water in the pipe and therefore...

Charging a System with an Indoor TXV

Charging a system with an indoor TXV is different from charging a system with a fixed metering device. TXV’s merely require a full line of...

Combustion Testing and Why It’s Important

As you may have noticed, there has been a slight chill in the air. Sorry to be the bearer of bad news, but you all...

High Head Pressure on Heat Pumps

Diagnosing a heat pump that is tripping on high head pressure in heating mode can be a challenge. With three service ports to choose from...

How safe is the home that you’re entering?

Hello all! I have a question. How safe is the home you are entering and how safe is that home when you leave? Do you...

How to Determine and Overcharged Unit with a TXV

When a unit is slightly overcharged with a TXV metering device, both suction and...

How to Improve Your Mitsubishi Troubleshooting

Hello Everyone! Mitsubishi makes some of the most efficient and comfortable systems available. If you have ever installed a Mitsubishi unit, then you know it...

How to measure CFM using the temperature rise method

A number of years ago, when I first moved into my house, I noticed an issue with my AC unit. When we ran the AC,...

Isolating a Furnace, Bypassing the Thermostat

Every day we receive many calls from frustrated technicians who are dealing with error codes on furnaces that, seemingly, can only be explained by a...

Measuring CFM’s Using Temperature Rise

In heating systems where airflow through the cabinet appears to be a problem, it can be difficult to determine the exact air volume that is...

Test In – Test Out

When performing a diagnostic it is important to fully diagnose the issue. Here is a way to ensure a correct diagnosis and to avoid expensive...

Test In – Test Out

When I started in the HVAC industry, I was taught a method of testing that has served me well for several years. It’s called “Test...

Testing a Single or Two Stage Gas Valve

Gas valves are an integral part of any furnace. They supply fuel to the burners, which enables ignition to take place. Gas valves have many...

The Stormy Season is on the Way

We all know how losing power can inconvenience you. The loss of lights, TV, cooking devices, HVAC equipment. Have you ever thought about how much...

Triple Evacuation

Many HVAC Techs have heard the term “triple evacuation”. What is a triple evacuation? Why do it? A triple evacuation is a very simple method...

Why Do Evaporator Coils Fail?

We have all seen or diagnosed a bad or poorly performing evaporator coil. Over my years in the eld, I have diagnosed bad coils and...

How to Test a Flame Rod

Proving flame is an important part of the sequence of operation. There are many ways to “prove flame,” but we will focus on...

How to measure CFM using the temperature rise method

A number of years ago, when I first moved into my house, I noticed an issue with my AC unit. When we ran the AC,...

The Difference Between Wet and Dry Bulb

When starting up an air conditioner it is important to measure wet bulb and dry bulb temperatures...

HVAC Service Work: Tools of the Trade

"What tools do I need?" Answering this can be complex, as the required tools vary depending on the specific job. This article will focus on essential tools for technicians engaged in HVAC service work.

Zoom Lock Fittings

One of the most important parts of extending the life of an AC unit or heat pump is ensuring that the refrigerant system stays...

The Right Tools for the Job

Nowadays, newer furnaces require the proper tools for efficient and correct diagnostics. The days of an analog meter and a book of matches are gone...

Cold Weather is Coming

Sorry to break it to you, but cold weather is coming. Before you start throwing tomatoes my way, this is only some advice to help...

Drop in Refrigerants

There has been a lot of commotion regarding ‘drop in’ refrigerants and I would like to clear some things up. Because of the rising price...