Jim’s Blog

In-house training programs for HVACR technicians can be broken down into three categories. First, there’s the process of bringing on new hires, or bringing someone up from installation to service, and making sure that this group has the fundamentals training they need in order to become an effective service technician. Second, there’s the seasoned technician who needs to be brought up-to-date on new developments and the equipment changes that are a result of that ever-evolving process in the HVAC industry. And, the third category applies to both of these groups…. their professional development from the perspective of interpersonal skills; customer service and communication skills, and, of course, sales skills.

 A Fundamentals Perspective

One of the major challenges that service managers and contractors deal with when training a new technician is what I refer to as haphazard experiences. What I mean by this is that when a technician in training is assigned to ride along on service calls, the experiences are haphazard simply because of the way a technician’s service day rolls out. The first call of the day may be a package unit heat pump with an air flow or refrigeration system problem. The second one can be a split system that employs a gas furnace as an air handler, and the third can be another type of system, etc….etc…. throughout the day. And regardless of how effective a senior technician is at explaining specific components, test procedures, and replacement of a failed part, a  significant percentage of the learning comes about in fits and starts, which means that for the trainee, it can be a jumble.

To keep the confusion that is a characteristic of the field training experience, your trainee needs structure. A training program that provides a logical sequence of the absolute fundamentals of electricity, refrigeration, and air flow, and serves two purposes: First, to eliminate the mystery behind things like current flow and the laws of thermodynamics, and second, to give trainees someplace to put the mountain of information that comes their way on a daily basis.

When it comes to lesson content regarding electrical fundamentals, the topics that help a new technician bring it all together are these:

…Electrical generating stations and the electrical grid

…Fundamentals of conductors, semi-conductors and insulators

…Schematic symbols and the structure of wiring diagrams

…Component identification and tracing circuits, the difference between loads and switches

…Proper use of test instruments and electrical safety, voltage, resistance, and amperage measurements

On the refrigeration side:

…Fundamental laws of thermodynamics that allow refrigeration systems to transfer heat

…The four basic components of any refrigeration system

…The refrigeration cycle and the state of the refrigerant as it enters and exits components

…Refrigerants and oils

…The temperature-pressure relationship between refrigerants and temperature/pressure charts

…Evacuation, dehydration and refrigerant recovery procedures

…The relationship between refrigeration system operation and proper indoor and outdoor air flow

…Proper use of gauges and coil temperature splits

…Fundamentals of superheat and subcooling

 And, when it comes to air flow:

…Properties of air

…Psychrometric charts and how they illustrate basic heating and cooling processes

…Air volume and velocity, and static pressure in a duct system

…Air flow measurement devices

With these very fundamental topics covered in your in-house training program, you’ve laid the foundation for further study on the more detailed subjects of HVACR system performance, electrical and refrigeration system evaluation and troubleshooting, and how to use manufacturer specific information regarding servicing and troubleshooting procedures.

We’ll continue our discussion on this subject in Part Two.

Learn from yesterday….Live for today…..Look forward to tomorrow





A large part of life is about milestones. And this post is a milestone for me, being as it’s my 100th post on this site.

Hitting this number was a goal that I set back in May 30th, 2011 when this site was set up as a replacement for our old one, and my objective in writing on the subjects of HVACR electrical troubleshooting, refrigeration systems, air flow, soft skills development for technicians, service management, in-house training, coaching, leading, managing, doing business on the web, technician certification, licensing, paying HVAC technicians, etc…was to approach it from the idea that I wanted to help anybody who was interested in reading what I had to say.

Looking back on it, I think the best way to describe my belief about blogging is that a large part of the philosophy behind the process is to consider it from the unconscious incompetence to unconscious competence perspective.

The easiest way to understand this concept is to consider tying our shoes.

When we were very young, we didn’t know how to tie our shoes, and we didn’t know that we didn’t know how to do that, which is defined as unconscious incompetence.

As we got a little older, we still didn’t know how to tie our shoes, but at some point, we realized that we didn’t know how, which is what conscious incompetence is.

So, we worked on learning to tie our shoes, and it wasn’t exactly easy, so we had to concentrate on doing it just so for a period of time before we mastered the process. This is conscious competence.

At some point, we developed the skill so we didn’t have to work so hard on tying our shoes, and we just started doing it automatically, which is unconscious competence.

We went from unconscious incompetence to unconscious competence with the two necessary steps of conscious incompetence and conscious competence in between.

I think that being a HVACR professional fits into the same learning model as tying our shoes. When we start out, there’s a lot of things we don’t know, and we don’t know that we don’t know them. But, once we’re aware that there are some things we need to learn, we concentrate on learning these things. and some of these skills, no matter what we’re applying them to, become automatic; a basis for the specific things we need to do in order to troubleshoot and service equipment.

Whether you’ve read every one of my posts here, or if you’ve only read a few, I hope that I’ve been a helpful source for you,  no matter where you might have been on the unconscious incompetence to unconscious competence continuum before you took the time to consider what I had to say. 

In wrapping up this post that is significant to me because it is, as I said above, a milestone. And since it’s a fact that nobody achieves anything of a significant nature all on their own,  I need to say thank you, first of all to two people who have made this possible.

First, my wife Peggy, who always supports everything I do and is directly responsible for any success I have achieved. And also, thanks to Valerie Lancaster of Wowsers Web Design for her expertise in developing and maintaining our site (and putting up with me in the process) on which this blog appears.

And thanks to those of you who have read some or all of this blog and commented and suggested and critiqued what I’ve written. It’s been my pleasure to put this stuff up here for you.

Learn From Yesterday….Live For Today….Look Forward To Tomorrow


I noticed some discussion lately on Linked-In about NATE and what some of the opinions are out there about it. One of the things I read about it was the idea that the organization has become more interested in perpetuating itself than in certifying technicians. This is where my question about jumping the shark comes  from.

The phrase “jumped the shark” was coined when, according to the opinion of some people involved in the production of the TV series Happy Days, the show reached a point where it was more about ratings than it was about telling its story and entertaining viewers. The episode was about the character Fonzie and his proving he was brave by water skiing, and ultimately jumping over a shark in the water. Actually, it was more of a gimmick than it was a story, and so, for many, it is considered a turning point when the production became more about earning revenue from high ratings than staying true to its original intent. And, what has happened to the phrase “jumping the shark” is what usually happens to a newly-coined phrase that came about due to some very specific situation. It is now often used to refer to any situation in which a negative, such as greed, has overcome what is considered to be the original honorable intent of an organization.

So, my question is, has NATE jumped the shark?

Well, I won’t pretend to know the answer to that question, but there are some things that I do know about the process of technician certification.

I know that even though there may be situations in which every question on a certification exam may not be valid according to everyone working in the field, the exam process itself still speaks to the overall understanding that technicians have in regard to their craft when they achieve a passing score on that exam.

I know that when the certification process works as intended, which is to both increase and measure the overall understanding a technician has about an industry, it results in increased confidence and competency.

I know that when confidence and competency increases, it results in a higher quality of work being performed by persons in their craft.

I know that when a higher quality of work is being performed by persons in their craft, it raises the standards of their industry.

I know that when the standards of an industry are raised, it results in a better end product or service for the consumer.

And I know, as everyone else also knows, that is the honorable intent of any business or industry.

So, like I said, I won’t pretend to know the answer to the question about NATE jumping the shark, and I don’t know that anyone can answer it for certain. All I can say is that if something isn’t perfect, then engaging in a dialogue about it is a good thing because that’s how we get as close as we can to perfect in any honorable effort.

And I know that increasing the confidence and measuring the competence of HVAC technicians is an honorable effort.


Learn From Yesterday….Live For Today…..Look Forward To Tomorrow



The bottom line on the proper and efficient operation of any HVAC system is that the air flow through the duct system has to be correct. If it’s not, then any other segments of the equipment operation such as the refrigeration system, fuel-burning system, or resistance-heat system, simply cannot perform as they are designed. The end result of this imbalance of operation between the equipment segments is poor performance that wastes energy and money, and can even become a safety and health concern for the building occupants.

 What this means is that specific measurements must be accomplished to ensure proper operation of the equipment, and one way to approach this task is to use an in-duct hot wire anemometer and a traverse measurement system in the main supply plenum. A digital device such as the one shown in Figure One that is capable of monitoring air temperature as well as measuring volume and velocity, allows you to enter duct sizing information, and has the capability to average so you can accurately calculate the total air flow, will tell you if there is sufficient air flow overall through the equipment. In a comfort cooling system, this accomplished simply through the process of accurate measurement in a duct, and then comparing the information you obtain to the manufacturer’s standard recommendation of 400 CFM per ton of equipment capacity.

Figure One

Figure One

Determining possible traverse locations for measurement applies to both rectangular ducts and round ducts, a sample of each of which is shown in Figures Two and Three.

Figure Two

Figure Two


Figure Three

Figure Three

With a fundamental understanding of traverse locations, a technician can use available tables and other information to consider the proper procedure for determining traverse air flow testing in a specific situation. As an example, consider the equipment shown in Figure Four where the supply plenum is shown positioned on the air handler cabinet.


Figure Four

Figure Four



For our purposes, we’ll determine that the duct assembly has a width of 24” and, because of that factor, we have chosen five traverse locations in a position on the plenum that is far enough away from the air handler. These five points are the locations for drilling a 3/8” hole in the duct. To accomplish the traverse measurement process, the probe of our anemometer will be inserted slowly through each opening until the tip of the probe touches the inside of the duct on the opposite side from our measurement  position. During each insertion, the anemometer will be set to take a measurement, and those measurements will be averaged to tell the technician what the total air flow measurement is in CFM.

In the event that the air flow is found to be insufficient, steps can be taken to modify the duct system or adjust the fan speed in order to ensure a proper balance between the air flow and refrigeration systems in the equipment.

In Part One of our discussion on total external static pressure testing of HVAC systems, we discussed checking the manufacturer’s installation information to determine what the TESP should be in a given system. As our chart showed, there isn’t just one number that applies to all systems regardless of the tonnage and the amount of air being moved by the indoor air handler.

However, one general application rule we can consider when evaluating any system in regard to the static pressure in the duct system is that most manufacturers of residential and light commercial equipment don’t want a pressure difference of more than .50″ W.C.  if a standard PSC, multiple-speed motor is employed by the air handling system. If the system employs a variable-speed, ECM-type motor, the TESP can be higher that that of PSC systems.

And, when it comes to evaluating an HVAC air flow system and going beyond the aspect of  isolating a given component in the duct system, such as the filter as we showed in the last segment, exact positioning the probes in the proper place varies, depending on the specific design of the system. For example, if you were evaluating a split system that employed a gas furnace as an air handler with an indoor coil positioned in the upflow position, Figure One shows you where you would effectively test the TESP of the blower itself in this particular type of system.

Figure One

Figure One

In this illustration, you’ll note that we have positioned the probe on the return side of the system after the filter so we can be sure we’re getting information directly at the inlet of the squirrel cage assembly of the blower. And when it comes to the probe on the supply side of the system, it’s positioned so that it is ahead of the indoor coil. Testing at these two points will tell us if the air handling system is operating properly in regard to the furnace itself, providing proper air flow through the duct system and the heat exchanger in the furnace. You’ll also note that we are just slightly above the general ‘.50 or less’ rule we mentioned for PSC blower assemblies. As we mentioned in the last segment on this subject, accomplishing static pressure tests provides us with the information we need to pursue a complete evaluation of the equipment operation and correct any potential problems affecting the total air flow through the duct system. If this system was a PSC rather than a variable-speed motor, we would need to expand our testing in order to bring the TESP across this blower down, and ensure the proper operation of this equipment.

Learn From Yesterday….Live For Today….Look Forward To Tomorrow


When it comes to the improper proper operation of an HVAC system, incorrect air flow is the number one cause of the malfunction. And one way for technicians to understand air flow in an HVAC system is to understand the concept of external static pressure.

A major factor regarding the performance of the air handling system is the static pressure that will exist between the negative side of the system (the return) and the positive side of the system (the supply). From a practical standpoint, a manufacturer’s blower performance chart (see Figure One) dictates what the TESP…Total External Static Pressure… is allowed to be in a given system.

Figure One

Figure One

In our illustration you can see that this chart is specific to two particular equipment models. When considering the high speed mode of blower operation on the chart, then following the CFM listings to the right until you find the block that shows 1311 CFM, you can then follow up to the top of the chart to the E.S.P listings to see that in this particular case, the manufacturer’s specifications state that the maximum TESP allowed is 0.4” WC (Water Column Inches). What this specifies is that when all items that would contribute to pressure drop in the air handling system are considered, including the filter, the ductwork itself, an indoor coil, and the air supply registers and return grilles, this is the maximum TESP that should be measured. A measurement beyond that number indicates that the performance of the air handling system, and therefore the performance of the refrigeration system and its ability to transfer heat, is being affected, preventing the equipment from operating at peak efficiency.

In the event that a test of a system accomplished with either a Magnehelic or a digital manometer showed a higher-than normal static pressure, the next step would be to perform tests on individual components to find out what steps could be taken to bring the equipment up to its intended operating standards. For example, isolating the filter and performing a static pressure test there, could reveal a simple solution to an overall static pressure that exceeds manufacturer’s specifications. (See Figure Two)

Figure Two

Figure Two

In this case, you’ll note that we have a static test probe positioned on either side of the filter in the return duct, and our Magnehelic is showing a pressure of less than .20” WC. The factor to consider here is that if the measurement at this or any other point in the system gave us enough room to be within the manufacturer’s standards, the equipment would be on track to perform properly. However, if this number was excessive, it would indicate that action must be taken, and there is one fundamental factor that a we could consider here.

That would be whether or not the filter was of the proper design for this system. While a high-grade filter works in one particular system, the design of another system may dictate that filter with lower resistance would be required. And, if a consumer, incorrectly assuming that the more dense filter would be the right one use, installed one that was of improper design, this simple action could affect the overall performance of the air handling system.

Just one of the simple things we need to understand about troubleshooting an HVAC system.

Learn From Yesterday….Live For Today….Look Forward To Tomorrow



What if there was a way to create a 20-MPH wind that would surround a building on all sides and force air at that velocity against all four wall surfaces and the roof simultaneously, so that a building’s tightness (or lack thereof) could be determined? Well, there is a way to accomplish that seemingly impossible feat, and we’re showing how in Figure One (image courtesy of ESCO Institute).


Figure One

Figure One

 This illustration shows how a blower door test is accomplished in order to de-pressurize a building. From a technical standpoint, the 20-MPH wind isn’t the method of measurement, but, when the blower exhausts air out of a building and the manometer shows the test pressure being accomplished is -50 pa WRT (we’ll get back to this shortly), that’s fundamentally what is happening. And creating this positive pressure outside the building and, therefore, the negative pressure on the inside, will accomplish an evaluation of the building envelope that allows us to find out if the building is tight, or if it’s not. Of course, if it’s not, then energy is being wasted due to an unnecessary addition to the cooling load, And, while we’re on the subject of unwanted air finding its way into a conditioned space in a building, we’ll remind you that the indoor air quality is being affected due to the un-filtered and un-controlled introduction of outside air.

What a technician needs to understand about the pressure measurement process relative to blower door testing is that the scale being used, the Pascal (pa), is a very fine measurement that provides very specific information about the pressure in a building. Here’s one way to appreciate just how fine a measurement is being accomplished in a blower door test:

 ….1 PSIG is equal to 27.70 inches of water column, the scale that most technicians are familiar with and appreciate how precise it is when measuring things like fuel pressure or static pressure in a duct.

 ….0.2 inches of water column is equal to 50 Pascals.W

Which brings us to “WRT”. It stands for “With Reference To” and it is the acronym used to describe, as our illustration is showing, the difference in pressure inside the house WRT the outside pressure. With one tube from the digital dual port manometer connected to the blower door assembly, and the second tube positioned properly to the outside of the building, the accurate WRT measurement proves to the technician that the building is being de-pressurized to the point where building envelope leaks can be detected and corrected in order to minimize energy waste and cut equipment operating costs.


Learn From Yesterday….Live For Today….Look Forward To Tomorrow


This will be the last segment of this five-part series on the subject of paying HVACR technicians for the work they do; installing, troubleshooting, and servicing air conditioning equipment. And, while we started this discussion based on only the idea of whether or not a technician should be paid an hourly wage vs. earning commissions and bonuses, it has evolved into much more than just making a decision to go one way or the other. We’ve delved into the subjects of ethics and values, why someone might think they need to sell a customer something they don’t need,  and how a service organization can effectively manage a commission/bonus system for their technician and technician teams.

That’s actually the bottom line on this issue…the fact that, as always, it “starts at the top”. Which simply means in this case that a technician won’t sell a customer something they don’t need, cover up a mistake with more charges, or take any approach other than honesty and fairness with the customer as long as they know what the company they work with stands for (and won’t stand for!) and they receive constant support and guidance from all levels of management and supervision.

With that said, the final point I want to make here is about an employer providing opportunity for an employee. A company called Nuance, a small steel manufacturing company has a very simple philosophy regarding employee opportunity. They follow an approach of: “Hire five, who work like ten, and get paid like eight.” And it works. Their team bonus system that provides opportunity for their employees is the foundation for their performance on Wall Street, enabling them to consistently earn higher profits than their much larger competitors, not just for quarters in a row, but for years in a row.

And, while it’s obvious that 99.9% of HVACR organizations don’t have anywhere near the resources at hand that a steel manufacturing company…even a comparatively small one….has, that doesn’t mean that the fundamental philosophy that is the basis of their success won’t apply on a smaller scale. The philosophy, applied in a company that is large or small, is based on an harmonious employer/employee relationship. Not one that promotes the processes of “getting as much work as possible out of somebody for the least amount of expense” and “getting as much money as I can out of somebody for the least amount of effort possible”.

 And it’s not based in sell!, sell!, sell!, and add-on!, add-on!, add-on! through daily pump-em-up sessions that are designed  to allegedly motivate technicians to squeeze every possible dollar out of every possible customer in order to consistently increase that service call dollar average, because, after all, “that’s how you make as much money as possible for yourself and your family”.


It’s based in the understanding that the mission of the service department is to provide the maximum value for the customer’s money spent while giving them every opportunity to make a buying decision about the things they need and/or want relative to the equipment in their home that keeps them and their family comfortable, safe, and healthy.

And, the technical professional who embraces that mission, and follows it consistently, earns the right to the opportunity to be paid like a professional.

Learn From Yesterday….Live For Today….Look Forward To Tomorrow






I’ve made it clear in previous segments on this subject that I’m an advocate of paying technicians via an incentive system such as a commission based on a percentage of labor billed and parts sales, rather than a straight hourly wage regardless of how much revenue an individual generates. And in this segment, I’m going to discuss the Fear Factor.

One fundamental component of human nature is that we want to be secure. And when it comes to our work life, secure means that we are of the belief that we will be able to bring home enough money on a weekly basis so we can pay the bills directly related to the survival and safety of ourselves and those who are part of our immediate family, and have some left over to save, and cover the cost of hobbies, entertainment, and vacations. Of course, if we are not of the belief that all these things are OK, that’s where the Fear Factor comes in.

When it comes to technicians working on a commission basis, the Fear Factor can be more than a gnawing irritant. It can loom large, causing constant worry, thereby affecting their work and the way they treat customers.

The underlying reason behind the Fear Factor is the belief that the day could come when there are not enough service calls to run on a given day, which would result in reduced revenue for the technician who is paid on a straight commission basis. This fear can  linger for some technicians no matter what history would show about the consistency of a service organization, and there are some simple ways to deal with it.

One way is to have a back-up system established; one that provides some kind of guarantee that should a series of events ever occur that would drastically effect revenue, the technician will go home with a given amount of money at the end of a pay period. Even though this back-up will never be needed  because a quality service organization is constantly in a situation where they always have enough work to go around, it puts people’s minds at ease, reducing the Fear Factor. And, in the end, it provides an environment in which technicians can concentrate on doing the best job they can do for their customers, which perpetuates an increase in volume, which allows them to be even more confident and relaxed and not affected by the Fear Factor, which perpetuates an increase in volume, which…well, you get the idea.

Another approach to keeping technicians on track while pushing the Fear Factor down even further is to establish a quarterly bonus system. If there are at least three technicians in a service department, making this a team bonus can be a good idea. Camaraderie within a group is a phenomenon we can all understand and appreciate, and it’s undeniable that the end result of group of people working together for a common good results in performance far beyond average.

Overall, when technicians are working within a system that pays commission based on their labor revenue and a bonus based on profitability, it goes toward dealing with that age-old problem of people leaving to “go into business for themselves” because they are, in essence, “in business” for themselves already when they are employed by a company that offers commission and bonuses. It’s just that their choice in “business” has been to have one client…..their employer, and they are actually in a best-of-both-worlds situation because of their decision. Their overall risk is minimized. They don’t have to be concerned about marketing, advertising, accounting, bookkeeping, parts inventory, vehicle operating expenses, collections, etc…and the list goes on and on.

All they need to do is concentrate on doing what they do best, and they wind up getting paid for their hard work and dedication to their craft.

Learn From Yesterday….Live For Today…Look Forward To Tomorrow


In Part Two of this discussion I presented the idea that some employers operate their business from the standpoint of lack and limitation rather than from the belief in abundance and opportunity. And, as a result of that negative approach, come off as stingy or someone who just uses technicians as a means to end to make a lot of money. Another offshoot of an owner or service manager taking this view is that it sets the stage for technicians who are paid on a commission basis to be less-than-honest when it comes to installing parts and completing service calls.

With this management approach, what often happens is that morning meetings are a negative event. The “numbers” are presented, and those who achieve the highest dollar average per call are praised for their efforts in maximizing volume. And it’s abundantly clear to those who have a lower dollar average that they need to find a way to bring their revenue up. Not just because it will put more money in their pocket, but because an environment like this instills fear that they might be fired if they don’t perform better dollar-wise. To put it simply, it’s an atmosphere of negativity, and it can foster irrational behavior. A technician may start out certain that they would never sell a customer something they didn’t need or want, but the fearful environment can slowly and steadily erode the technician’s belief system, and “justify” something that a month before would not have happened.

Of course, this approach to doing business is doomed to failure in regard to the retention of certain employees. A person can only be lead just so far down the path of “justification” before they decide that they must leave this type of environment. They begin to take steps to make the transition to another workplace as painless as possible for themselves and their family, hanging on where they are until they can be sure that the losses that can occur with a change in employment are minimized. And inevitably, they leave.

A technical professional who is competent in troubleshooting and diagnosis, performing repairs,  and communicating with customers is lost; the situation labeled simply as ’employee turnover’. And the expense of recruiting and hiring goes on and on through the revolving door of this service department.

And, then, there’s the technician who doesn’t leave. And the reason this person stays is because while they, like the employee described above,  harbor fears about money running out and the pie only having just so many pieces, their ethics and belief system allows them function in this type of environment. Not necessarily happy and professionally fulfilled, but functioning.

My point here is that paying technicians via an incentive system isn’t an evil thing to do….unless the people running the show are OK with it being evil, and they recruit technicians who agree with them.

Learn From Yesterday….Live For Today….Look Forward To Tomorrow



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