The 12 Biggest Mistakes Installers Make With Goodman’s New R-32 Systems
(And How to Avoid Them — Mike’s Brutal Truth Edition)
Goodman’s new R-32 systems — like the GLXS4BA3610 condenser paired with the 3.5-ton CHPTA4230C3 coil — are efficient, powerful, and built to run smoother than the old R-410A units ever did.
But only if the installer knows what they’re doing.
And let me tell you something that’s going to hurt a little:
Most installers do NOT know how to properly install an R-32 system.
I’ve been called out to fix more “brand-new” R-32 installs in the last year than I ever expected — and almost every problem was caused by installer error, not equipment failure.
From improper line-set prep to high static pressure to incorrect TXV seating, these mistakes kill SEER2 performance, ruin airflow, burn out compressors, and create noise that could wake the dead.
If your installer does ANY of these?
Stop the job.
Immediately.
Let’s dive in — Mike style.
1. Reusing Old Line-Sets (The #1 R-32 System Killer)
Installers who reuse old line-sets should lose their gauges.
Old copper contains:
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mineral oil
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old POE oil
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microscopic debris
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copper scale
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moisture
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acid formation from previous refrigerant breakdown
R-32 is more chemically sensitive than R-410A.
Contamination RUINS it.
The [A2L Refrigerant Transition Handling] clearly states:
R-32 MUST be installed with new, clean, properly insulated copper line-sets.
Reusing old lines isn’t “shortcutting.”
It’s system sabotage.
2. Not Pulling a Deep Vacuum (500 Microns or Lower)
“Good enough” isn’t good enough for R-32.
If the vacuum pump barely hits:
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1,000 microns
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bounces around
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rises too fast
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doesn’t hold
…the system isn’t dry.
Moisture + R-32 =
acid + oil breakdown + premature compressor death.
The [Refrigerant Circuit Moisture Removal ] shows R-32 needing stricter dehydration than older blends.
If your installer doesn’t have a digital micron gauge?
They aren’t qualified for R-32.
3. Charging By “Beer Can Cold” Instead of Scale + Subcooling
If your installer grabs the suction line and says:
“Yeah, feels cold. It’s good.”
Fire them.
R-32 demands:
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factory-specified refrigerant weights
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precise subcooling
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stable superheat
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correct TXV positioning
R-32’s efficiency hinges on accurate charge.
Guessing is death.
The [Goodman Factory R-32 Coil Commissioning Addendum] states the charge MUST be verified by WEIGHT plus performance readings.
Old-school methods won’t work here.
4. Undersizing the Return Duct (Instant Noise + Static Problems)
A 3-ton system with a 3.5-ton coil needs:
14–16" return minimum
Most homes have:
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10" return
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one hallway grille
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cheap 1" filters
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tight return bends
That creates:
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noise
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turbulence
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blower strain
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coil freezing
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compressor overheating
High static pressure is the silent system killer — confirmed in the [Residential System Balance , which shows static pressure >0.6" can reduce cooling output by 20–40%.
If your installer won’t measure static?
They’re guessing.
5. Installing the Horizontal Coil Without Correct Pitch
Horizontal coils MUST be pitched toward the drain — or condensation floods the pan and spills into your ceiling.
Pitch must follow:
¼" per foot of run
The [Horizontal Coil Requirements Note] highlights improper pitch as a top cause of attic water damage in R-32 installs.
If your coil is “perfectly level,” your attic is perfectly doomed.
6. Forgetting to Install a Secondary Pan + Float Switch (Rookie Mistake)
Especially with horizontal coils.
Every attic install MUST include:
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secondary drain pan
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float safety switch
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properly sloped primary drain
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trap + cleanout
Skipping this is negligence.
One clogged drain is all it takes for a $10,000 ceiling disaster.
7. Incorrect TXV Bulb Positioning (Kills Efficiency)
TXV bulb errors cause:
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starvation
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flooding
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coil freeze-ups
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pressure swings
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unstable superheat
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reduced SEER2 retention
The TXV Bulb Placement & Refrigerant Metering Stability Guide shows incorrect bulb placement can cut cooling capacity by up to 32%.
TXV bulb must be:
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strapped tight
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insulated properly
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placed at 4 or 8 o’clock
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mounted on a horizontal suction line (never vertical)
Bad TXV setup = bad performance.
8. Not Using Vibration Isolation on the Condenser Pad
R-32 compressors run smoother but more responsive — without proper isolation they transmit vibration through:
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deck
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patio slab
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walls
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foundation
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line-sets
Leads to:
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humming
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buzzing
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rattling
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pipe resonance
The Condenser Vibration Dampening & Mounting Specification emphasizes isolation risers for lightweight concrete pads.
Noise isn’t normal.
It’s preventable.
9. Improper Line-Set Routing Causing Oil Traps & Line Whistle
Bad routing = refrigerant starvation.
Common rookie mistakes:
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uphill suction run with no traps
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unnecessary loops
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tight kinks
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line rubbing against wood or metal
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long horizontal runs with no support
R-32 flows FAST and loudly through bad geometry.
The Refrigerant Line Geometry & Acoustic Resonance Study shows that poor routing can increase noise by 40%+ and reduce TXV stability.
Proper routing matters.
10. Failing to Seal the Coil Cabinet & Plenum (Massive Efficiency Loss)
Horizontal setups pull attic air into the system through tiny cracks.
That hot air:
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raises humidity
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raises suction temp
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makes coil sweat
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destabilizes TXV
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increases runtime
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destroys SEER2
The HVAC Cabinet Air Leakage Thermal Loss Memo shows that even small cabinet leaks can drop efficiency by 10–20%.
Mastic + foil tape = huge performance gain.
11. Skipping Airflow Testing (Because “It Blows Cold”)
This is malpractice.
Your installer MUST measure:
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total external static
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CFM
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temperature split
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duct pressure loss
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return velocity
If they don’t?
Your system isn’t commissioned.
A Goodman R-32 system needs PROOF of proper airflow — as required in the Air Handler Commissioning & Performance Confirmation Checklist.
“Feels good” isn’t engineering.
12. Not Balancing the System (The Killer of Comfort)
Unbalanced systems cause:
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hot rooms
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cold rooms
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humidity pockets
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long run times
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noisy vents
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poor comfort stability
Balancing supply dampers and return pathways isn’t optional — it’s required for any 3-ton system to deliver full performance.
Bad balancing = unhappy homeowner.
**Mike’s Final Verdict:
Goodman R-32 Systems Are Incredible — But Only If Installed Correctly**
Here’s the blunt truth:
✔ R-32 demands more precision
✔ Goodman engineered these systems for efficiency, not installer shortcuts
✔ 90% of R-32 issues are installer mistakes
✔ A proper install = 20-year lifespan
✔ A sloppy install = 5–7 years of pain
If your installer doesn’t:
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replace the line-set
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measure static
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pull deep vacuum
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test airflow
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verify charge
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pitch the coil
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install safety switches
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use proper routing
…then the job isn’t done.
A GOOD installation is quiet, efficient, cold, and stable.
A BAD installation is loud, expensive, inefficient, and short-lived.
Do it right once.
Enjoy the system for decades.
That’s the Mike way.
