The HVAC/R Diagnosis Pyramid of Skill


It was my first few weeks out of tech school, and I had already ridden with several guys. Some good, some not as good, but today was the first time with this tech, and something was already different. We were driving to our first call of the day, and between dirty jokes and puffs on a cigarette, he said:

“OK, let's guess what's wrong with this next one… they are all Lennox in this subdivision… so I'm betting… a TXV.”

That was my first exposure to the “Been there, seen that” tech who relies on calibrated guesswork as a primary diagnostic tool. Along the way, I've met many more of these and other types of techs in the “Diagnosis Pyramid,” and so I will share them with you now.

But first…

I confess: I stole this pyramid idea from “Graham's Hierarchy of Disagreement,” which is also one of my favorites. Maybe I just like pyramids. My grandmother was an ancient alien, so there's that.

The Hack

I literally just made a podcast where I said we should stop calling people hacks. So, I guess I'm a hypocrite, but “hack” is much easier to say than “tradesperson of dubious skills, training, or intellect,” so hack will need to suffice here.

Many hacks think they know what they are doing because they suffer from a heavy dose of the Dunning-Krueger effect and stand firmly on Mt. Stupid, as shown here.

The good news is that many confident people start here, and this is not a life sentence to stay stranded on Mt. Stupid. I have done complete hack jobs in my career, thinking I had enough skill, knowledge, and experience, only to realize later that I was a bumbling goon. The hack has to travel through the valley of despair to reach the slope of enlightenment, where they can become a real tech.

Strength = Ignorance is Bliss

Fatal Flaw = They Are Terrible at Working on HVAC/R 

White Shirt

Let's start by focusing on the good things about a white shirt:

  1. They smell nice
  2. They smile
  3. They have a firm handshake
  4. They rarely break systems because they don't use tools on them very often

The truth is that many good techs could learn a thing or three about positive communication and people skills from a white shirt, but that is where my positive comments end.

The trouble with white shirts advancing beyond that stage is that they have no incentive to do so. They don't need to get dirty, they make lots of money, and they look dang good doing it.

These are just salespeople, and the more technical material they learn, the more complicated it can be to sell systems, so why bother?

Strength = Making Money & Looking good

Fatal Flaw = Greed 

Parts Changer 

There are two types of parts changers: the one who does it to make more money and the one who does it because he thinks that's what diagnosis is.

In flat rate environments that pay bid time or commission on parts, some techs catch on quickly that certain repairs are money makers, so they look EXTRA HARD for those repairs on every job. It isn't to say they are purposefully looking to pad a ticket, but they become fixated on certain things that bring in the most money to them.

The other parts changer is often an inexperienced or under-trained tech who throws a bunch of parts at a problem and honestly thinks that's how you fix problems.

I knew one tech who would replace the control wire and transformer every time he encountered a low voltage fuse blowing for a reason he couldn't figure out. He didn't do it because it benefitted him in any way; he just didn't know how to troubleshoot.

Strength = They Eventually Get The System Running (Mostly)

Fatal Flaw = It Costs a Lot and Often Requires Multiple Trips 

Been-There Tech

The been-there tech is common in all industries, especially in techs who have done the job 10+ years. When you start as a hack or a parts changer, it's often easier to end up relying on what you've seen before than it is to go back to the start and really understand the fundamentals of how things work.

It can be a big ego hit for a been-there tech to admit what they don't understand, so they often form complex legends to explain why things happen the way they do.

Been-there techs will often talk about “weird problems” and will concoct strange solutions to problems, such as drilling holes places you are pretty sure they shouldn't or wiring this or that to that other thing or bypassing that one part because “it's not really needed.”

The been-there tech should do more manual reading and less storytelling, and they will find that the myths and legends begin to look more like science.

Strength = They Often Have a Lot of Valuable Experiential Knowledge 

Fatal Flaw = What They Know Only Applies to What They've Actually Worked On; New Technology is Often Confounding

Average Tech 

The final four techs are all truly techs, and they have more in common than they have that separate them. The majority of the techs you meet that can actually repair most problems on most machines are average techs.

An average tech generally knows how the system works, can use a gauge manifold and a meter, and can figure out the location of a leak or a low voltage short.

Their focus is on diagnosing the primary problem, fixing it, and getting out of there as quickly as possible. They don't do much with superheat or subcool, though they know how to calculate it. They don't use a micron gauge, though they know the “right” answer is 500 microns, and they don't really care to learn much more.

Strength = They Can Consistently Make Stuff Blow Cold and Hot

Fatal Flaw = Callbacks are Pretty Common When “More Stuff Breaks”

Senior Tech 

A real senior tech has all the find-and-fix skills of an average tech but with extra insight into the “why” behind a failure. Yes, the TXV is restricted, but WHY wasn't the factory drier replaced with a new one when that compressor was replaced 6 months ago?

A senior tech knows how a compressor works and what makes it fail, knows how to check combustion on a furnace and what is causing the rising CO, and can spot a leaking flare fitting from a mile away.

The thing that keeps a senior tech from becoming a super tech is the difficulty to envision more than one layer beyond the “NOW” cause to all of the contributing factors that are often outside of the equipment itself.

You'll see this when the senior tech encounters issues like high or low humidity, sweating ducts, occupant discomfort, coils that keep leaking over and over, or consistent compressor failures when all the readings look “fine.”

When issues start to spread outside of the equipment into the electrical system, indoor air, envelope, ducts, and design, a senior tech can find themselves frustrated.

Strength = Excellent Diagnosticians 

Fatal Flaw = Appliance Fixation 

Super Tech

The term “super tech” is often used as a pejorative to mean an experienced tech who thinks they know it all. These types of super techs are often actually “been-there” techs who like to talk on social media.

No, here I'm defining “super tech” as a tech that can really fix just about anything with enough time allotted. They are nerdy enough to fill any knowledge gaps they may have about an issue before they call it good. They diagnose the entire structure and notice all of the contributing factors to problems. You can throw this sort of tech at almost any problem, however…

They still are all about solving problems and can miss opportunities to optimize performance.

Strength = They Can Fix Anything 

Challenge = They Aren't Always That Profitable 

Unicorn Tech 

Ok, I'm stretching here, but let's face it, this whole thing is a bit of a stretch.

In order for a really good tech to also optimize profitability, they need to look outside of what is wrong in need of fixing and what can be improved for optimal:

  • System longevity
  • Efficiency
  • Comfort
  • Indoor health & safety

Doing this really well is a heck of a lot more than just selling a UV light or PCO, as many white shirts do; it's about really understanding how to fine-tune a building and equipment to work better.

These are things like dropping the compression ratio on a rack by letting the head float a little lower or recommending that can lights be replaced with sealed LED trim to reduce attic infiltration.

There are many high-value solutions that HVAC/R techs can help to suggest and implement that lead to a profitable business and happy customers.

Strength = Living Happily Ever After 

Fatal Flaw = Too Much Money that They Must Build a Tower Like Scrooge McDuck to House (Ok, more like pride in their work and good night's sleep—leave the gold tower to the white shirts.) 



Ted Kidd
Ted Kidd
12/30/19 at 09:15 PM

DAMN that’s good. Wish I’d written it!


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