Checklist Before You Power On: Final Prep Tips for Installing the GLXS4BA3610 + GR9T961005CN

Oh Hey There, HVAC Bosses! 😎

It's your girl Savvy Mavi, reporting live from the land of leak-free installs and flawless airflow. If you’re staring lovingly at your newly-installed Goodman GLXS4BA3610 R-32 condenser and GR9T961005CN 96% AFUE gas furnace, STOP ✋ before you flip that switch and fire it up.

You’re not quite done. Not yet, sweet cheeks.

There’s a pre-start checklist—and not the kind you scribble on the back of an invoice. I'm talking about a legit, field-tested, Savvy-certified check-every-box-or-regret-it-later kind of list.

Ready? Let’s make sure your system powers on without a hitch. ✨

1. Verify Equipment Matching 🧩

Let’s start with the most basic—but most commonly skipped—step. Is your Goodman system fully matched and AHRI-certified? If it’s not, you're risking:

• Efficiency loss

• Performance hiccups

• And most importantly, a voided warranty

Cross-check your full system (GLXS4BA3610 condenser + CAPTA3626C3 coil + GR9T961005CN furnace) at the AHRI Directory to confirm they're listed as a certified combo.

If you see your AHRI number pop up? Boom. ✅ You're golden.

2. Confirm Line Set Integrity & Refrigerant Prep 🔧

Now let’s talk line sets—the unsung heroes of HVAC installs. Whether you ran new copper or reused an existing set (with a deep clean, I hope), you need to:

• Verify line set length and diameter matches spec

• Pressure test the lines with nitrogen to ≥300 PSI

• Pull a vacuum to 500 microns or lower—yes, 500, not 1500!

Need a deeper dive on microns and vacuum technique? Check out this straight-up amazing guide from HVAC School.

Important: Since we’re dealing with R-32 refrigerant (hellooo, low GWP superstar 🌍), you also need to follow A2L safety procedures. That means:

• No open flames nearby

• Proper ventilation during charge

• A2L-certified leak detection tools

Want to keep it pro? Use the EPA’s Section 608 A2L update guide for refrigerant safety info that’s actually helpful.

3. Furnace Wiring & Polarity Check ⚡️

Alright, let’s shift focus to the GR9T961005CN gas furnace. This thing is a beauty, but she’s picky about her electrons.

Before flipping that disconnect:

• Verify line voltage polarity (yes, hot and neutral do matter)

• Confirm ground wire is securely bonded

• Inspect low-voltage connections for:

  • Thermostat (R, C, Y, W, G)

  • Float switch (if used)

  • Condenser signal wire

Quick test: Grab your multimeter and confirm 24V between R and C at the furnace board. No volts = no go.

Bonus tip: If you’re using a fancy Wi-Fi thermostat like a Nest or ecobee, make sure it’s compatible with a multi-stage furnace. Some models need a common wire or extra accessory relay. Energy Star has a handy compatibility guide for those.

4. Double-Check Drainage & Venting 💦💨

If you want to avoid mid-summer pan floods or winter furnace lockouts, don’t skip this step.

For the coil:

• Verify primary & secondary drain lines are clear and properly trapped

• Add a float switch (Savvy’s pro tip—always)

• Pitch the pan downhill, baby

For the furnace:

• Ensure proper condensate drain from the secondary heat exchanger

• Verify venting material is PVC or CPVC only

• Pitch vent pipe ¼" per foot back toward furnace

The Goodman GR9T series is a Category IV appliance, which means it’s condensing. Any slope mistakes, and your system could be swimming inside.

5. Airflow & Duct Pressure Testing 🌬

Don’t let those sweet SEER2 numbers go to waste—test your airflow before startup!

Checklist:

• Filter clean & correctly sized

• Return duct sized for 400 CFM per ton minimum (so about 1200 CFM for 3 tons)

• No blocked or undersized registers

• Blower settings configured correctly (check the dip switches or ECM board)

Use a static pressure test kit and aim for ≤0.5" WC total external static. Too high = airflow restriction and short cycling. Not cute.

6. Burner Assembly & Gas Pressure 🔥

Now we’re heating up—literally.

Before lighting the fire on that GR9T961005CN, confirm:

• Gas line size matches spec (usually ¾" or larger for 100k BTUs)

• Sediment trap is installed (hello, code compliance!)

• Inlet gas pressure = 5"–10" WC for NG

• Adjust manifold pressure to manufacturer’s spec (3.5" WC typically)

Light it up and:

• Check flame color—should be blue, stable, with no yellow tips

• Verify ignition sequence and flame sensor signal ≥1.0 microamps

• Confirm blower kicks on after delay

7. Test Mode Sequence 💡

Before calling it done, always run the system through a test mode:

1. Set thermostat to cool

2. Confirm condenser starts, indoor blower runs, suction line starts to sweat

3. Switch to heat

4. Observe full burner sequence, inducer operation, and blower delay

Let the system run for 15–20 minutes in each mode to monitor:

• Superheat & subcooling

• Combustion CO levels (target <100 ppm CO air-free)

• Static pressure and temperature rise

Record all readings and document them for warranty and commissioning purposes. 💼

8. Register Your System 📲

Don’t forget this one—it’s boring, but important.

Register your Goodman system at Goodman’s Warranty Registration within 60 days of install. Otherwise, that 10-year parts warranty drops to 5 years.

Also keep a paper trail of:

• AHRI match confirmation

• Installer license info

• Startup readings and install photos

If anything goes sideways later? You’ll be so glad you documented everything.

Final Thoughts from Your Favorite HVAC Fairy Godmother 🧚🏽

There you have it, my loves. A no-fluff, all-fab pre-power-on checklist for the Goodman GLXS4BA3610 and GR9T961005CN system.

Look, HVAC install isn't about just "hooking stuff up." It’s about performance. Reliability. And making sure your customer’s comfort doesn’t come with callbacks or costly do-overs.

So run this checklist like a boss, flex your install skills, and enjoy the sweet reward of a perfectly tuned system. 🔥❄️

Need the full system? Snag it now from The Furnace Outlet.

Need more troubleshooting tips for the GR9T961005CN? Visit: Troubleshooting Gas Furnace Start-Up Issues: Understanding the GR9T961005CN Logic.

Until next time, keep it level, leak-free, and luxuriously efficient,
— Savvy Mavi Out!