What Actually Happens During a Klein Cooling AC Maintenance?
We’re not maintaining your air conditioner just to make it clean. We’re looking for the thing that’s trying to break next.
There is a version of HVAC maintenance that goes something like this:
Spray condenser.
Pour something down drain.
Look at capacitor.
Change filter.
Slap sticker on air handler.
Write:
“SYSTEM OPERATING NORMALLY 👍”
Leave.
Technically, several maintenance-related activities have occurred.
But at Klein Cooling, that’s not really what we mean by preventative maintenance.
Our goal isn’t simply to leave you with a cleaner air conditioner.
Our goal is to answer a much more useful question:
Is there anything happening inside this system right now that could become a breakdown, water problem, performance issue or expensive repair later?
That’s an entirely different job.
And we didn’t invent this methodology for a blog article.
This article is based on our actual Klein Cooling Preventative Maintenance Training Manual.
It’s the same methodology we use to train our technicians.
We recently spent a Saturday class doing exactly this on the system at our own shop: working through a maintenance from beginning to end, taking measurements, testing components, discussing what the numbers actually mean and learning how to recognize a healthy HVAC system.
Because if we’re going to send somebody into your house to tell you whether your air conditioner is healthy, we’d prefer their training consist of slightly more than:
“The capacitor is the silver thing.”
Especially because qualifying Klein Cooling maintenance plans include our No Breakdown Promise.
If we’re willing to put our name behind that promise, we’d better do considerably more than give your condenser a bath twice a year.
So here it is.
The actual method.
First: Is This Actually a Maintenance?
Before we get into preventative maintenance, we need to discuss a particular type of customer.
You know who you are.
You scheduled your maintenance three weeks ago.
Wonderful.
Then Monday comes.
The air conditioner stops working.
Your maintenance appointment is Thursday.
You could call us Monday and say:
“Hey, just so you know, the AC stopped working.”
But no.
You look at the calendar.
You see Thursday.
And apparently think:
“Perfect. They’re coming Thursday anyway.”
So you wait.
Monday.
Tuesday.
Wednesday.
Thursday morning arrives.
Technician pulls into the driveway with his maintenance bag.
“Good morning! How’s everything been running?”
And only then do you casually mention:
“Oh, actually it hasn’t worked since Monday.”
SIR.
This is no longer preventative maintenance.
THE THING HAS ALREADY BEEN PREVENTED FROM WORKING.
We have crossed over into a service call.
Or, Even Better: You Don’t Tell Us At All
This is the advanced version.
Technician arrives.
“Have you noticed any problems with the system?”
“Nope.”
Beautiful.
Thermostat calls for cooling.
Nothing happens.
Technician checks the thermostat.
Checks the air handler.
Heads outside.
Starts troubleshooting.
Meanwhile, the homeowner is standing approximately eight feet away watching this unfold.
Ten minutes later:
“Yeah, it started doing that Monday.”
…
MY BROTHER IN CHRIST.
That was relevant information.
We weren’t making conversation when we asked if you’d noticed any problems.
You are allowed to tell us.
Actually:
WE ENCOURAGE IT.
You do not receive bonus points if the technician independently discovers the problem.
This isn’t Undercover Boss.
Then There’s the “Maintenance” Because Something Seems Weird
Customer:
“I’d like to schedule an AC maintenance.”
Absolutely.
We arrive.
Start talking.
“Well, the bedroom hasn’t really been cooling.”
Okay.
How long?
“About three months.”
Anything else?
“Sometimes it makes this horrible grinding noise.”
Okay.
Anything else?
“Every couple days I have to shop-vac the drain or the whole thing shuts off.”
Ma’am.
You did not call for maintenance.
You called for an exorcism and selected the wrong appointment type.
Please Tell Us What Your Air Conditioner Has Been Doing
Underneath the jokes, this actually matters.
Our preventative-maintenance process assumes we’re evaluating an operating HVAC system.
If there is already a known malfunction, we need to diagnose it.
That’s a different process.
And intermittent problems are especially important.
If it stopped cooling Tuesday afternoon and started again:
Tell us.
If the thermostat went blank:
Tell us.
If the evaporator froze:
Tell us.
If you saw water:
Tell us.
If the outdoor unit made a noise that sounded like somebody throwing a shopping cart down a staircase:
DEFINITELY TELL US.
HVAC equipment possesses an extraordinary ability to behave perfectly the moment a service truck enters the neighborhood.
What you observed matters.
We’d much rather know about it before we start.
What Is Preventative Maintenance Supposed to Prevent?
This sounds like an incredibly stupid question.
It isn’t.
Preventative maintenance.
The clue is right there in the name.
We’re trying to prevent things.
A dirty condenser is one of those things.
A clogged drain is another.
But we’re also looking for:
- deteriorating electrical components,
- loose or overheated connections,
- abnormal motor operation,
- developing water problems,
- refrigerant issues,
- airflow problems,
- corrosion,
- failed or failing safeties,
- abnormal system performance,
- and anything else suggesting the equipment isn’t behaving the way it should.
Because if your technician spends an hour at your house and the contactor looks like it fought in Vietnam but nobody mentions it…
What exactly were we preventing?
The Klein Cooling Maintenance Method
Our training methodology follows a deliberate sequence:
LOOK → RUN → MEASURE → INSPECT → CLEAN → TEST → RUN AGAIN → DOCUMENT
The order matters.
One of the first things we teach is:
Don’t disturb the evidence before you’ve looked at it.
You wouldn’t arrive at a crime scene, pressure-wash everything and then start looking for fingerprints.
Unless you’re the murderer.
Same idea.
Let’s go to work.
Step 1: LOOK
Touch nothing.
Seriously.
Put the hose down, Turbo.
Before we clean anything, adjust anything, clear anything or start taking things apart, we want to see the system the way it exists every other day when we aren’t standing there.
Remember one of the first rules from our maintenance training:
Don’t disturb the evidence before you’ve looked at it.
Start with the homeowner.
Has anything changed?
Any unusual noises?
Any water?
Any rooms not cooling properly?
Longer run times?
Humidity issues?
Thermostat doing anything weird?
Has the system shut off unexpectedly?
Sometimes the answer is:
“Nope. Everything’s been great.”
Beautiful.
That’s useful information.
Sometimes the answer is:
“Well… except it hasn’t worked since Monday.”
There he is.
Put the maintenance checklist down for a minute.
We’ve got some diagnosing to do.
And if something weird has been happening—even if the system is working perfectly while we’re standing there—tell us.
HVAC equipment possesses an extraordinary ability to correct every intermittent problem approximately 30 seconds before the service truck pulls into the driveway.
If it froze last Tuesday, tell us.
If the thermostat went blank twice, tell us.
If you saw water underneath the air handler, tell us.
If the outdoor unit occasionally makes a noise that sounds like somebody throwing a shopping cart down a staircase:
DEFINITELY TELL US.
That information matters.
And Then We Ask About the Filter
At some point, your technician is going to ask:
“When was the last time you changed the filter?”
This is not an accusation.
It’s a routine question.
And yet, for some reason, it immediately turns into a deposition.
“Oh, we change it every month.”
Excellent.
We pull the filter out.
It has developed its own ecosystem.
We look at the date somebody thoughtfully wrote on the side.
It’s dated somewhere after COVID but before 2024.
Interesting.
Nobody says anything.
Technician looks at filter.
Homeowner looks at technician.
Technician looks back at filter.
The filter has now become Exhibit A.
It’s okay.
We understand.
We tell the dentist we floss every day too.
Nobody is going to jail.
Just tell us the truth.
Because the answer actually matters.
A dirty filter can restrict airflow, affect system performance, contribute to coil problems and make some of the measurements we’re about to take considerably more interesting.
And please don’t feel like you need to change it five minutes before we arrive, either.
That’s like cleaning your house before the cleaning lady gets there.
We actually want to see how the system has been operating.
The condition of that filter is information.
So when we ask:
“How often are you changing your filter?”
You can tell us.
Even if the answer is:
“Apparently sometime during the first Biden administration.”
We’ll figure it out.
No judgment.
Well.
Maybe a little judgment.
But we’ll keep it professional.
Now Look at the Equipment
With the customer interrogation complete, still don’t start cleaning.
Look first.
We want to inspect the equipment in the condition we found it.
We’re checking for things like:
Water staining.
Rust.
Corrosion.
Oil staining.
Deteriorated insulation.
Damaged wiring.
Overheated connections.
Biological buildup.
Drainage problems.
Loose components.
Evidence of previous water problems.
And generally:
Anything that looks like it shouldn’t look like that.
Look around the air handler.
Look underneath it.
Look at the primary and secondary pans.
Look at the drain.
Look at the insulation.
Look at the wiring.
Look at the outdoor unit.
Look at the line set.
Look at the disconnect.
Look at the equipment before you start making it prettier.
Because sometimes the system is already telling you exactly where you should be paying attention.
A water stain isn’t just ugly.
An oily spot isn’t just dirty.
A discolored terminal isn’t just old.
A rusty component isn’t automatically bad, either.
They’re clues.
And clues require investigation—not assumptions.
That distinction matters.
We’re not walking around trying to find something we can condemn.
We’re looking for evidence that tells us where we may need to investigate further.
A surprising amount of HVAC diagnosis begins with using the two diagnostic instruments installed directly beneath your eyebrows.
Use them before you use the hose.
Once we’ve looked at the system as we found it, talked to the homeowner, inspected the filter and documented anything unusual…
Now we’re ready to see what the equipment actually does.
Which brings us to:
Step 2: RUN
Before we make the system better, we want to know how it was operating before we touched it.
Turn it on.
Let it stabilize.
Listen.
Look.
Feel.
Then establish a baseline.
Depending on the equipment and conditions, we’re looking at things such as:
Indoor temperature
Indoor relative humidity
Return-air temperature
Supply-air temperature
Temperature difference
Outdoor ambient temperature
Why do this before cleaning?
Because if you immediately wash the condenser, clear the drain, change something and then take your first measurements, you’ve lost something valuable:
The condition in which the customer was actually operating the equipment.
We want the before picture.
Step 3: MEASURE
There are two ways to inspect an air conditioner.
Method A:
“Looks pretty good.”
Method B:
“The capacitor is rated at 45/5 µF and measured 44.2/4.9. Compressor current is X against a nameplate value of Y. Blower current is X. Return air is X, supply air is Y, indoor relative humidity is Z…”
Guess which one makes it onto our Performance Report.
Numbers don’t replace judgment.
They give judgment something to stand on.
What Are We Measuring Indoors?
Our Preventative Maintenance Performance Report records the important operating information from the system.
Depending on the equipment and what we’re evaluating, that can include:
Return-Air Temperature
What’s going into the system?
Supply-Air Temperature
What’s coming out?
Temperature Difference
What did the equipment actually accomplish between the two?
And no:
“20 degrees” is not one of the Ten Commandments.
Temperature split is useful information.
It is not a magical number that single-handedly diagnoses an HVAC system.
Indoor Relative Humidity
Because we’re in Florida.
We aren’t merely trying to make your house cold.
We’re also trying to keep it from feeling like a refrigerated swamp.
Blower Amperage
What is the motor actually drawing?
How does that compare with its rated information and operating conditions?
Voltage
Because electrical equipment tends to be somewhat particular about electricity.
Static Pressure — When Appropriate
What’s happening with airflow through the system?
Is the equipment breathing normally?
Or is it trying to breathe through a straw?
That’s useful information.
Step 4: INSPECT
Now we get to the heart of the methodology.
A maintenance technician isn’t just asking:
“Is this component working?”
We’re also asking:
“Is there evidence that this component may not continue working?”
Those are very different questions.
The Capacitor Is Not a Vibe Check
Please stop looking at capacitors and declaring them good because they aren’t swollen.
We measure them.
If the label says:
45/5 µF
we want to know what it actually measures.
Then we compare the measurement with the manufacturer’s allowable tolerance.
Because:
“It looked capacitor-ish.”
is not a diagnostic measurement.
Inspect the Contactor
Look at the contacts.
Look at the terminals.
Look for overheating.
Look for deterioration.
Look for loose connections.
Look for evidence.
And this part matters:
We are not looking for an excuse to sell a contactor.
We’re looking for evidence that a problem exists or may be developing.
There’s a difference.
A slightly ugly component is not automatically a failed component.
Welcome to Florida.
If we replaced everything that looked ugly after sitting outside here for five years, we’d be replacing your condenser, your mailbox, your patio furniture and half of Palm Coast.
Check the Motors
Compressor amperage.
Condenser-fan amperage.
Blower amperage.
Compare the measurements with equipment information and operating conditions.
Listen to them.
Inspect them.
Don’t just ask whether it runs.
Ask whether anything about its operation gives us a reason to investigate further.
A motor can be running today while quietly preparing to ruin somebody’s Friday next month.
We’d like to meet it before then.
Look at the Wiring
Loose terminals.
Heat discoloration.
Damaged insulation.
Corrosion.
Rubbed wiring.
Anything suggesting:
“This is going to become somebody’s no-cool call at 4:47 PM on a Friday.”
We would prefer to meet that wire today.
Step 5: CLEAN
Okay.
Now you may have the hose.
Clean the outdoor coil as appropriate.
Remove accumulated dirt and debris interfering with heat transfer.
Florida condensers have a difficult life.
Heat.
Humidity.
Pollen.
Grass.
Salt air near the coast.
And whatever your lawn guy launched directly into the coil at approximately Mach 3.
Keeping that coil clean matters.
But notice where cleaning appears in our methodology.
Step Five.
Not Step One.
Because preventative maintenance is not synonymous with:
“I own a hose.”
The Drain Is Not a Side Quest
If you’ve been in HVAC in Florida for more than eleven minutes, you already know.
A clogged condensate drain can shut the system down.
A drainage problem can damage ceilings.
It can damage flooring.
It can damage equipment.
It can make everybody involved have a very bad Tuesday.
So we take condensate seriously.
We clear and flush the drain.
We inspect the primary pan.
We inspect the trap.
We verify actual drainage.
We check for leaks.
We test the float protection.
And there are two particular drain rules in our training manual that deserve their own sections.
The first one was purchased through experience.
DO NOT USE NITROGEN TO CLEAR A CONDENSATE DRAIN
Yes.
It gets all caps.
We bought this rule.
A condensate drain is typically PVC. It may run through an attic, wall, chase or finished ceiling, with glued fittings that you cannot see.
Do not turn that drain into a pressure vessel by blasting nitrogen through it to clear a clog.
Ask us how we know.
Once upon a time, we had a technician clearing a condensate drain in a roughly $2 million oceanfront home.
Nitrogen went in.
Clog cleared.
Drain looked good.
Technician packed up.
Everybody lived happily ever after.
For a few hours.
There was just one small issue.
The pressure had blown apart a concealed PVC drain connection.
Nobody knew.
Until later that night.
When the homeowner discovered the problem using the traditional method:
WATER STARTED POURING THROUGH THE CEILING.
That was a fun phone call.
So when one of our technicians sees:
DO NOT USE NITROGEN TO CLEAR A DRAIN
in the training material, this isn’t some theoretical rule we copied from the internet.
There is a story behind it.
And probably an invoice.
Clear the drain using an appropriate method that doesn’t pressurize the PVC piping.
Then:
Verify actual water flow.
Check for leaks.
Inspect the pan.
Test the float protection.
And then we arrive at Drain Rule Number Two.
FILL. THE. TRAP.
After clearing the drain:
Refill and prime the condensate trap with water.
It’s incredibly easy to clear a drain, congratulate yourself on a job well done, pack everything up…
…and leave the trap empty.
Depending on the equipment configuration and pressure relationship, that can interfere with proper drainage.
So our Performance Report specifically requires us to document it.
TRAP FILLED / PRIMED WITH WATER AFTER DRAIN CLEANING ✓
We don’t want:
“I think I did.”
We want:
✓
There are certain lessons in HVAC you learn from textbooks.
There are others you learn after driving 35 minutes back to somebody’s house.
We prefer the textbook ones.
Step 6: TEST THE FLOAT SWITCH
Looking at a float switch is not testing a float switch.
Read that again.
A float switch can be:
present
and also:
not doing a damn thing.
So we test it.
Does it actually shut down what it’s supposed to shut down?
Great.
Then:
RESET IT.
Please.
Nothing says “comprehensive preventative maintenance” quite like creating a no-cool call in the driveway.
Technician finishes maintenance.
Customer signs paperwork.
Technician leaves.
Customer:
“It’s getting warm in here.”
Technician, halfway to Ormond:
“……..the float switch.”
Turn around, hero.
Step 7: Refrigeration — When Appropriate
This is another place where we don’t want technicians simply attaching gauges because:
“It’s maintenance. That’s what you do.”
Every measurement should answer a question.
When refrigeration measurements are appropriate, our Performance Report gives us places to document readings such as:
Suction pressure
Liquid pressure
Suction-line temperature
Liquid-line temperature
Superheat
Subcooling
Metering-device type
Those numbers tell a story when interpreted together and in context.
What we don’t teach is:
“Pressure looked a little low. Added two pounds.”
Absolutely not.
Know what you’re measuring.
Know why you’re measuring it.
Know what the expected result should be.
Then interpret what you actually found.
The gauges are measuring instruments.
They are not a refrigerant vending machine.
Step 8: RUN IT AGAIN
You’re finished cleaning.
Drain is clear.
Trap is filled.
Float is reset.
Panels are back on.
Everything looks beautiful.
Time to leave?
Nope.
Run the system again.
Because:
WE TOUCHED IT.
We want final operating readings.
We want to make sure the equipment operates correctly after our maintenance.
We want to make sure the drain is actually draining.
We want to make sure nothing is leaking.
We want to make sure we didn’t create a problem.
And we want to compare final operation with what we observed when we arrived.
It’s the HVAC equivalent of:
“Did you save the file before closing the computer?”
Just do it.
Step 9: Ask the Question Behind Our No Breakdown Promise
Before finishing, the technician should ask:
Would I be surprised if this system broke down before its next maintenance?
Not:
“Is it running right this second?”
That’s an incredibly low bar.
We want to know whether everything we’ve seen, measured, inspected and tested gives us reasonable confidence in the system’s condition.
If the answer is:
“Yep. Everything looks and measures good. I’d be surprised if something failed.”
Excellent.
But if the answer is:
“Ehhhhhhhhh…”
Don’t close the tool bag.
Figure out what the “ehhhhhhh” is.
Maybe the amperage is abnormal.
Maybe a connection looks overheated.
Maybe a motor sounds wrong.
Maybe a capacitor is approaching the edge of its allowable tolerance.
Maybe you found water somewhere water shouldn’t be.
Maybe the numbers simply don’t make sense together.
That does not mean:
SELL SOMETHING.
It means:
INVESTIGATE SOMETHING.
Huge difference.
Our No Breakdown Promise Is Not Magic
Mechanical equipment can fail.
Electrical components can fail unexpectedly.
Lightning exists.
Florida exists.
Geckos apparently have an ongoing personal vendetta against electrical equipment.
We cannot predict every failure.
The promise changes how seriously we approach maintenance.
If we’re putting our name behind the equipment between visits, we have every incentive to identify a developing problem before you’re sitting in an 87-degree house.
That’s why our methodology is built around:
Inspection.
Measurement.
Testing.
Documentation.
Not just cleaning.
Step 10: The Final Walk-Around
Before leaving, stop.
Drain flowing?
✓
Checked for leaks?
✓
Trap filled?
✓
Float switch tested?
✓
Float switch RESET?
✓
No water where it shouldn’t be?
✓
Panels installed?
✓
Disconnects and breakers restored appropriately?
✓
Thermostat returned to the customer’s desired setting?
✓
Tools accounted for?
✓
That last one is important.
There are few moments in life more humbling than cruising down I-95, reaching for your meter and suddenly remembering exactly where it is.
Sitting on top of Mrs. Johnson’s air handler.
In Palm Coast.
You are currently in Daytona.
Enjoy your drive.
Step 11: Give the Customer the Performance Report
This is where everything comes together.
We don’t want the final record of an hour-long maintenance to be:
“Completed PM. System OK.”
What does that tell anybody?
Nothing.
Instead, every Klein Cooling preventative maintenance uses our standardized:
Klein Cooling Preventative Maintenance Performance Report
And since we’re apparently publishing the internal playbook now…
Here it is.
That is not a special website version.
We didn’t add a bunch of impressive-looking boxes for this article.
That’s the actual report.
It’s the same standardized Performance Report our technicians use on our preventative-maintenance jobs.
Same equipment information.
Same indoor readings.
Same outdoor readings.
Same electrical measurements.
Same refrigeration readings when applicable.
Same condensate and safety checks.
Same cleaning items.
Same findings and recommendations.
Same report. Every maintenance.
That’s intentional.
Because comprehensive maintenance shouldn’t depend on whether the technician happened to remember everything that day.
The methodology teaches the technician how to evaluate the system.
The Performance Report makes sure we document what we actually did and found.
And the customer gets the results.
Think of the Performance Report as the Receipt for the Work
Not the bill.
The receipt for the work.
If we tell you:
“Your capacitor tested good.”
There’s a measurement.
If we tell you:
“Your compressor is operating normally.”
There’s an amperage reading.
If we tell you:
“Your system is cooling properly.”
There are temperature readings.
If we cleared your drain:
There’s documentation that we verified drainage, checked the safety and primed the trap afterward.
The customer shouldn’t have to simply take our word for it that we performed comprehensive maintenance.
We should be able to show them.
And when we come back for the next maintenance, we gain something else:
HISTORY.
Now we aren’t only asking:
“What’s the compressor drawing today?”
We can also ask:
“What was it doing last time?”
That’s when individual measurements can start becoming trends.
And trends can tell us things that a single snapshot can’t.
We Are Not Hunting for Repairs
Preventative maintenance is not:
“Find three things wrong before leaving.”
There is no requirement that an air conditioner produce an upsell because somebody opened the service panel.
Sometimes we thoroughly inspect a system and find:
Nothing.
Beautiful.
That’s a successful maintenance.
Sometimes we find something worth monitoring.
Sometimes something deserves additional testing.
Sometimes we find a legitimate repair.
Our rule is the same:
Find evidence. Measure it. Understand it. Explain it.
If we can’t tell the customer what we found, how we tested it, what the measurement was and why it matters, we probably shouldn’t be telling them to buy something.
And sometimes the right recommendation really is:
“Let’s keep an eye on it.”
That’s still doing our job.
For the Technician: Learn What Normal Looks Like
This may be the most important part of our training methodology.
Maintenance is one of the best training opportunities an HVAC technician will ever get.
Think about it.
The equipment works.
Nobody’s panicking.
The house isn’t 91 degrees.
The compressor isn’t screaming.
The customer isn’t standing six inches behind you asking:
“So… do you know what it is yet?”
You have an operating refrigeration system sitting in front of you.
Study it.
Measure it.
Listen to it.
Look at it.
Ask why.
Why is the suction line cold?
Why is the liquid line warmer?
Why did the amperage change?
Why is there a temperature difference across the evaporator?
Why does static pressure change?
Why does the air leaving the condenser feel warmer than the air entering it?
Why does the drain need a trap?
Why does the float switch shut the system down?
Don’t just collect numbers because the Performance Report has blank spaces.
Understand what the numbers mean.
Because eventually you’re going to stand in front of a system where something is wrong.
And here’s the problem:
You can’t recognize abnormal if nobody ever taught you normal.
That’s why we practice this on our own equipment in class.
We’re not teaching technicians how to fill out a checklist.
We’re teaching them how to look at an HVAC system.
The Checklist Is Not the Method
A checklist is useful.
Obviously.
We literally created one.
But the checklist exists to make sure important steps aren’t forgotten.
It does not replace thinking.
If your entire maintenance methodology is:
Capacitor ✓
Contactor ✓
Drain ✓
Coil ✓
Blower ✓
Temperatures ✓
you haven’t necessarily evaluated anything.
You have demonstrated excellent penmanship.
After every measurement, there should be another question:
SO WHAT?
Compressor amps are 6.2.
So what?
Capacitor measures 43.1.
So what?
Temperature difference is 17°F.
So what?
Indoor relative humidity is 62%.
So what?
Does the reading make sense?
Is it within specification?
Does it agree with the other measurements?
Has it changed from the previous visit?
Does it tell us to test something else?
That’s where a technician starts becoming a technician.
A Clean Air Conditioner Is Not Necessarily a Healthy Air Conditioner
This may be the simplest explanation of our entire maintenance philosophy.
You can have a beautifully clean condenser connected to:
A weakening capacitor.
An overheated terminal.
A deteriorating contactor.
A noisy motor.
A drainage problem.
A refrigerant issue.
An airflow problem.
A float switch that doesn’t actually work.
Or…
A system that is operating absolutely perfectly.
The garden hose cannot tell you which one you have.
Inspection can.
Measurement can.
Testing can.
And documentation gives us a record of what we found.
So What Actually Happens During a Klein Cooling Maintenance?
The entire methodology from our Preventative Maintenance Training Manual can be reduced to this:
LOOK → RUN → MEASURE → INSPECT → CLEAN → TEST → RUN AGAIN → DOCUMENT
And throughout the process, the technician keeps asking:
What is this system telling me?
What should this measurement be?
What did I actually measure?
Does that make sense?
Is there evidence of something beginning to fail?
Is there a water risk?
Does something need further testing?
And finally:
Would I be surprised if this system broke down before we come back?
If we’ve answered those questions, cleaned the equipment, serviced the drain, tested the safeties, verified operation and completed the Performance Report…
Now we’ve performed preventative maintenance.
If we just sprayed the condenser and left?
Well.