Klein Trade Program — Week 17
Job Ready: Split Systems, Nameplates & Our First Full Preventative Maintenance
Saturday, August 15, 2026
Job Ready Certificate Training — Split Systems, Equipment Nameplates, Tools & Preventative Maintenance Lab
Welcome to Week 17 of the Klein Trade Program.
Last week was self-study.
Safety.
Customer interactions.
Professionalism.
This week?
Back to the shop.
And back to:
Job Ready Certificate Training.
Our classroom topics were:
Split systems.
Equipment nameplates.
Tools.
Then we went into the lab and put everything together by performing:
A complete preventative maintenance on our shop system.
Not:
“Go look at the air conditioner.”
Not:
“Check the capacitor.”
Not:
“See if it’s cooling.”
A complete inspection.
Measurements.
Cleaning.
Testing.
And:
Documentation.
Because if you didn’t write down what you measured?
Six months later, everybody gets to guess.
😂
Welcome to Week 17.
We’re Starting to Think in Complete Systems
Up to this point, we’ve spent a lot of time isolating individual concepts.
Here’s a capacitor.
Here’s a contactor.
Here’s a motor.
Here’s a thermostat.
Here’s superheat.
Here’s subcooling.
Here’s static pressure.
That’s necessary when you’re learning.
But the customer doesn’t call and say:
“Hello, I’d like you to inspect my capacitor in isolation from the rest of the HVAC system.”
😂
They have an HVAC system.
And now we’re learning to approach it that way.
Split Systems
We started with one of the most common configurations our students are going to encounter:
The residential split system.
It’s called a split system because the major equipment is split between indoor and outdoor sections.
Typically, we’re dealing with:
Indoor Equipment
Air handler or furnace.
Evaporator coil.
Blower.
Filter.
Heat kit where applicable.
Drain system.
Controls.
Outdoor Equipment
Condenser coil.
Compressor.
Condenser fan motor.
Contactor.
Capacitor or electronic components depending on the equipment.
Refrigeration controls.
And connecting the two:
Refrigerant lines and control wiring.
We’ve studied nearly every one of these components already.
Now we’re looking at them as one complete system.
Start With the Equipment
Before touching anything:
What are you working on?
This sounds ridiculously basic.
It isn’t.
Manufacturer?
Model?
Serial?
Refrigerant?
Voltage?
Minimum circuit ampacity?
Maximum overcurrent protection?
Factory charge?
Heating information?
Motor information?
Equipment capacity?
A lot of what you need to know is sitting right there.
Where?
The nameplate.
Read the Damn Nameplate
😂
This has become a recurring lesson for a reason.
The manufacturer put information on the equipment.
Use it.
Before you decide:
“That compressor is pulling too many amps.”
What’s it rated for?
Before deciding:
“That’s the wrong breaker.”
What does the equipment specify?
Before adding refrigerant:
What refrigerant does this thing even use?
Before replacing a motor:
What are the specifications?
Read first.
Then measure.
Model Numbers Tell Stories
Eventually technicians become surprisingly good at looking at model numbers.
Hidden inside those beautiful strings of seemingly random letters and numbers may be information about:
Capacity.
Series.
Voltage.
Configuration.
Efficiency.
And more.
Different manufacturers use different formats.
You’re not expected to memorize all of them.
That’s what manufacturer documentation is for.
But start paying attention.
Eventually you’ll look at a model number and immediately recognize pieces of it.
That’s part of learning the trade.
Serial Numbers Matter Too
The serial number can help us determine important information about the equipment, including its age.
That matters.
A reading on a two-year-old system and the same reading on a sixteen-year-old system may lead to very different conversations.
We’re not just collecting numbers.
We’re building a history of the equipment.
Which brings us directly to today’s lab.
Tools: Bring What You Need
We’ve already spent an entire class talking about HVAC hand tools.
And by Week 17, something funny has probably happened.
Remember Week 2?
Everybody:
“I’m going to keep my tools organized.”
😂
Uh huh.
Now we’re several months in.
There’s a marker missing.
One 6-in-1 has vanished.
Someone’s duct knife is living in an attic.
And your temperature probe may currently reside permanently in a supply plenum somewhere in Daytona Beach Shores.
Welcome to the trade.
But preventative maintenance requires a technician to arrive prepared.
If you’re just getting into the trade and building your first tool bag, we’ve already put together the list we wish somebody had handed us:
HVAC Hand Tools for New Technicians →
And yes:
Buy two 6-in-1s.
Trust us.
😂
What Tools Do We Need for a PM?
The exact setup depends on the equipment and what we’re evaluating, but a technician may need things such as:
Multimeter.
Temperature probes.
Static-pressure probes and a manometer.
Refrigeration probes or gauges when appropriate.
Basic hand tools.
Cleaning equipment.
Drain tools.
Flashlight.
Inspection mirror.
And:
Something to document the results.
Because today’s lesson isn’t just:
Take readings.
It’s:
Record them.
LAB: Full Preventative Maintenance
Now we’re putting the pieces together.
This week, the students performed a complete preventative maintenance on our shop system.
This matters because preventative maintenance forces you to look at the:
WHOLE SYSTEM.
You’re not arriving because one specific component has already failed.
You’re evaluating operating equipment and asking:
What is this system telling us today?
That’s a very different diagnostic mindset.
Step One: Look
Before pulling out every instrument you own:
LOOK.
Seriously.
Look at the equipment.
Look at the wiring.
Look at the drain.
Look at the coil.
Look at the blower.
Look at the refrigerant lines.
Look at the insulation.
Look for oil.
Look for corrosion.
Look for overheating.
Look for loose connections.
Look for water.
Look for anything that simply doesn’t look right.
Your eyes are diagnostic tools too.
They’re just not calibrated in microfarads.
😂
And there’s a reason we look before we start cleaning things.
Don’t disturb the evidence.
If there’s a water stain, oil residue, burned connection, corrosion or something else unusual, we want to see it before we make the equipment prettier.
Run the System
Before changing anything, let’s see how the system is actually operating.
Turn it on.
Let it stabilize.
Listen.
Observe.
Start establishing a baseline.
Depending on the equipment and conditions, that may include:
Indoor temperature.
Indoor humidity.
Return-air temperature.
Supply-air temperature.
Outdoor temperature.
Equipment operation.
Anything unusual?
Noise?
Vibration?
Water?
We’re trying to see the system as the customer has actually been using it.
Before we change the evidence.
Check the Filter
Start simple.
What’s the filter size?
What condition is it in?
Is it installed correctly?
Is it overly restrictive?
Is the filter rack reasonably sealed?
Remember Week 11:
The filter is part of the airflow system.
A dirty or overly restrictive filter can affect system performance.
And here’s another important lesson:
If the customer changed the filter five minutes before you arrived because they didn’t want you to see the old one?
😂
Well…
We lost some useful information.
We’re not judging.
Mostly.
We want to know how the system has actually been operating.
Inspect the Blower
Now we’re back to Week 13.
Inspect the blower.
Wheel condition?
Motor condition?
Amperage?
Operation?
Noise?
Anything unusual?
We’ve already learned how to replace a blower motor.
Now we’re evaluating one before it fails.
That’s an important difference between:
Repair
and
preventative maintenance.
Inspect the Evaporator Coil
Week 14:
We replaced one.
Week 17:
Inspect it.
Is it clean?
Is airflow reasonably unrestricted?
Any signs of corrosion?
Any evidence of refrigerant oil?
Drain pan condition?
Anything unusual?
Again:
We’re not looking for reasons to sell something.
We’re looking at the equipment and documenting what actually exists.
The Drain Is Not a Side Quest
Florida HVAC technicians will spend an unreasonable percentage of their lives thinking about water.
😂
Cooling creates condensate.
That water has to go somewhere.
So:
Inspect the drain.
Clear and flush it using an appropriate method.
Check the trap.
Inspect the pan.
Verify actual drainage.
Check for leaks.
Test float protection.
A relatively minor drain problem can become a very expensive ceiling problem.
Pay attention to the drain.
And if you want to know why some of our drain procedures are written in all caps…
There are stories.
And probably invoices.
😂
Electrical Inspection
Now our meter comes out.
Inspect electrical components.
Look for:
Loose connections.
Heat damage.
Discoloration.
Burned terminals.
Damaged wiring.
Contactor condition.
Capacitor condition.
And other equipment-specific items.
Then:
Measure.
The Capacitor Is Not a Vibe Check
😂
Week 15 comes right back.
Read the capacitor rating.
Measure the actual capacitance.
Compare it with the allowable tolerance.
Then:
Document the number.
Don’t write:
“Cap good.”
If it’s rated:
45/5 µF
write what it actually measured.
Why?
Because next time we have history.
Maybe today it’s:
44.2/4.9.
Next visit it’s lower.
Now we’re not relying on somebody remembering what happened six months ago.
We have data.
Motors and Amperage
Measure appropriate operating amperages.
Blower.
Condenser fan motor.
Compressor.
Compare those measurements with equipment information and operating conditions.
Again:
Don’t just write:
“Amps good.”
Write:
The actual numbers.
That’s useful information.
Temperatures
Return-air temperature.
Supply-air temperature.
Temperature difference.
Outdoor conditions.
Line temperatures where appropriate.
And remember:
A temperature split is information. It isn’t the entire diagnosis.
There isn’t one magical temperature difference that single-handedly tells us whether every HVAC system is healthy.
We’re building a picture.
One measurement at a time.
Refrigeration
When refrigeration measurements are appropriate for the equipment and what we’re evaluating, we take them correctly.
Suction pressure.
Liquid pressure.
Saturation temperatures.
Line temperatures.
Superheat.
Subcooling.
Now Week 14 comes right back.
But remember:
Connecting gauges isn’t the goal.
Understanding the refrigeration system is the goal.
Every measurement should answer a question.
Static Pressure
Hello again, Week 11.
😂
Static pressure gives us valuable information about the airflow system and what the blower is working against.
Take the measurement correctly.
Document it.
Compare it with manufacturer information and system conditions.
If static is high?
Don’t immediately declare:
“BAD DUCTWORK.”
Investigate.
Filter?
Coil?
Return?
Supply?
Blower configuration?
Duct restriction?
The measurement tells us something deserves attention.
It doesn’t automatically tell us why.
Now We Clean
Notice how much happened before we started washing things.
That’s intentional.
Now we can clean the appropriate components.
Outdoor coil.
Drain.
Accessible areas of the equipment.
Anything else included in the maintenance procedure.
The purpose isn’t simply to make the equipment look prettier.
We’re trying to maintain performance and reliability.
And when we’re finished?
We’re still not done.
Test the Safeties
A safety that nobody tests isn’t much of a safety inspection.
Float protection.
Electrical safeties where appropriate.
Equipment-specific protections.
Verify operation.
If something is supposed to shut the system down under a particular condition?
We want to know that it actually does.
Run It Again
This is where things get interesting.
We took initial readings.
We inspected.
We cleaned.
We performed the maintenance.
Now:
What changed?
Maybe airflow improved.
Maybe static changed.
Maybe temperature difference changed.
Maybe refrigeration readings changed.
Maybe nothing meaningful changed.
That’s useful too.
Now we’re learning:
Cause and effect.
Documentation Is Part of the Job
This was a major part of Week 17.
WRITE IT DOWN.
Not:
“Everything looked pretty good.”
Not:
“Unit cooling.”
Not:
“PM complete.”
😂
What did you actually measure?
What condition was the equipment in?
What did you clean?
What did you test?
What did you find?
What should be monitored?
What changed after maintenance?
That’s useful documentation.
The Same Maintenance Process We Actually Use
And here’s what makes this lab different from a random classroom exercise:
We didn’t create a special student version.
The students were learning the same basic preventative-maintenance methodology we use on actual Klein Cooling systems in the field.
Our process follows a deliberate sequence:
LOOK → RUN → MEASURE → INSPECT → CLEAN → TEST → RUN AGAIN → DOCUMENT
We’ve published the entire process in A/C University, including the Klein Cooling Preventative Maintenance Performance Report we’re training our technicians to use.
If you want to see exactly what we’re teaching in this class — and what we’re looking at when we maintain an HVAC system — here it is:
What Actually Happens During a Klein Cooling AC Maintenance? →
The form is right there in the article.
Not a watered-down homeowner version.
The actual method.
Because if we’re going to send somebody into your house to tell you whether your air conditioner is healthy, their training should probably consist of slightly more than:
“The capacitor is the silver thing.”
😂
Why Documentation Matters
Imagine we return six months later.
Different technician.
Customer says:
“They told me something about the capacitor last time.”
What was it?
Without documentation:
Who knows?
With documentation:
Rated: 45/5 µF
Previous reading: 42.8/4.9
Current reading: 40.7/4.8
Now we have history.
Same with:
Static pressure.
Refrigeration readings.
Motor amperage.
Temperatures.
Equipment condition.
Maintenance becomes a timeline instead of a snapshot.
That’s powerful.
Stop Writing “Good”
This is especially important for measurements.
Capacitor:
Good.
Compressor amps:
Good.
Blower amps:
Good.
Temperature split:
Good.
Static:
Good.
Wonderful.
WHAT WERE THE NUMBERS?
😂
Condition fields can say:
GOOD.
Yes/no questions can say:
YES or NO.
But measurement fields?
Actual measurements.
Because six months from now we want something to compare.
Take the Picture Before You Clean It
This is another lesson worth learning.
If you find:
Dirty blower wheel.
Corrosion.
Damaged insulation.
Burned wire.
Dirty coil.
Water staining.
Something unusual.
Take the picture before changing it.
Then, when useful:
Take another one afterward.
Now we have documentation.
And the customer can see exactly what we found.
No dramatic sales presentation required.
Just evidence.
Your Memory Is Terrible
😂
You take the compressor amperage.
You think:
“I’ll remember that.”
Then:
Customer asks a question.
Phone rings.
You move to the condenser fan.
You check the capacitor.
You flush the drain.
Ten minutes later:
“Was that compressor 6.2 or 6.8?”
No idea.
Write the number down when you take it.
That’s why we have a report.
Don’t Scare the Customer With Numbers
This is where Week 16 comes right back.
Customer interaction.
You find something worth monitoring.
Explain it.
Don’t say:
“YOUR STATIC IS .93! THIS THING IS ABOUT TO EXPLODE!”
😂
No.
Explain:
What we measured.
Why it matters.
What it could indicate.
Whether anything needs to be done now.
Whether we’re simply monitoring it.
And what we’re going to compare during the next maintenance.
Numbers should help customers make better decisions.
They shouldn’t be weapons used to scare somebody into buying something.
Maintenance Is Not a Sales Appointment
This matters to us.
The purpose of preventative maintenance isn’t:
Find something to sell.
The purpose is:
Inspect the system.
Measure operation.
Clean appropriate components.
Test safeties.
Identify legitimate concerns.
Document them.
Help the customer understand the condition of their equipment.
Sometimes we find a repair.
Sometimes we don’t.
Sometimes the system is old but operating fine.
That’s okay.
An air conditioner is allowed to be old.
😂
Our job is to report what we actually find.
The Numbers Don’t Exist to Sell Something
This might be one of the most important lessons we’re teaching.
Why are we measuring the capacitor?
To know its condition.
Why are we measuring compressor current?
To evaluate operation.
Why are we checking static?
To evaluate airflow.
Why are we taking temperatures?
To understand system performance.
The answer should never be:
“Because we need something to show the customer.”
We’re collecting information so we can make better technical decisions.
If everything looks good?
Excellent.
Tell the customer everything looks good.
That’s allowed.
😂
What Should a Student Know After Week 17?
This week brought a lot of previous lessons together.
By the end of Week 17, students should be more comfortable with:
- Identifying the major components of a residential split system
- Reading equipment nameplates
- Recording model and serial information
- Understanding why manufacturer specifications matter
- Selecting appropriate tools for maintenance
- Performing a structured visual inspection
- Establishing baseline operating conditions
- Inspecting filters and airflow components
- Inspecting the blower assembly
- Inspecting the evaporator and condenser
- Servicing the condensate drain
- Testing electrical components
- Measuring capacitors
- Measuring motor and compressor amperage
- Taking temperature measurements
- Taking refrigeration measurements where appropriate
- Measuring static pressure
- Performing appropriate cleaning
- Testing safeties
- Retesting after maintenance
- Recording actual measurements
- Documenting equipment condition
- Communicating findings without unnecessary fear or sales pressure
Most importantly:
We’re learning to evaluate the whole system.
From Individual Measurements to a Performance Report
This is a pretty big milestone.
At the beginning of the program, we were learning what the equipment was called.
Then we learned individual measurements.
Voltage.
Amperage.
Capacitance.
Pressure.
Temperature.
Superheat.
Subcooling.
Static pressure.
Now we’re putting those measurements into:
One complete picture of system performance.
That’s what a good maintenance report should be.
Not a checkbox saying:
“AC works.”
A record of what the equipment was actually doing on the day we inspected it.
Then next time?
We do it again.
And compare.
Now we’re not guessing whether something changed.
We know.
See You in Week 18
We’re documenting the Klein Trade Program week by week inside A/C University.
Week 17 looked a whole lot like something these students will eventually do in the field:
Arrive at a system.
Identify the equipment.
Talk to the customer.
Look before touching anything.
Run it.
Measure it.
Inspect it.
Clean it.
Test it.
Run it again.
Document everything.
Explain what you found.
That’s Job Ready.
Not because you memorized the answers.
Because you’re learning a process you can repeat on:
The next system.
And the next one.
And the next one.