Reading HVAC Proposals Like a Contractor Would

The $14,000 Mistake That Started With Three Little Words

“Trust me, sir.”

That’s what the contractor said to Tom Brennan, standing in his Frisco home’s driveway at 7 PM on a Tuesday in July 2023. Tom had just gotten home from work, his house was 87 degrees inside, and this guy with the magnetic truck signs was the third HVAC company to show up that day. The proposal? One paragraph on a carbon copy form. Total: $14,000. The entire equipment description: “New AC system.”

Tom signed it. Four weeks later, he called me to fix what they’d installed.

The 5-ton unit they’d slapped in was way oversized for his 2,400 square foot house. It short-cycled constantly – running for three minutes, shutting off for five, starting again. His electric bill jumped from $380 to $520. The humidity inside felt like a swamp because the system never ran long enough to actually dehumidify. They’d used his existing 20-year-old lineset without flushing it. No load calculation. No duct inspection. Just a big expensive unit that made everything worse.

I see the aftermath of these proposals every week across North Texas. Good people getting burned because they didn’t know what questions to ask or what that paperwork should actually say. So let’s fix that right now.

Why Contractors Write Bad Proposals (And Hope You Won’t Notice)

Here’s something most homeowners don’t realize: vague proposals protect contractors, not you.

When I worked for a big box HVAC company back in 2011 (won’t name names, but their trucks are everywhere), our sales manager literally trained us to keep proposals short and simple. His exact words: “Confused customers don’t argue about change orders.” The less detail we put in writing, the more wiggle room we had to upsell later or cut corners on installation.

Think about it. If the proposal just says “install new AC unit,” they can put in whatever brand they get the best deal on that week. Goodman? Carrier? Some off-brand they found at a liquidation sale? All technically meet the proposal requirements. Same goes for “install per manufacturer specifications” – sounds professional, but which specifications? The basic ones? The recommended ones? The ones that ensure your warranty stays valid?

A proper proposal should bore you with details. Mine typically run 3-4 pages minimum. Not because I like paperwork, but because spelling out every single component, procedure, and warranty term protects both of us. You know exactly what you’re paying for. I know exactly what I promised to deliver.

The contractors who hand you a sticky note with a price? They’re counting on you being too stressed about your broken AC to ask questions.

Breaking Down a Real Proposal (Line by Line)

Let me show you what I wrote up for the Hendersons in Plano last month. They needed a full system replacement after their 18-year-old Lennox finally gave up during that heat wave. Here’s what their proposal included, section by section:

Equipment Specifications (Should be at least half a page)

• Exact model numbers: Carrier 24ACC636A003 condenser, FE4ANF003 air handler
• Serial numbers once available
• SEER2 rating: 15.2
• Tonnage: 3-ton (based on Manual J calculation attached)
• Refrigerant type: R-410A
• Warranty details: 10-year parts through Carrier, registered within 60 days

Notice how specific that is? Not “3-ton Carrier” but the exact model that matches their home’s calculated cooling load. That Manual J calculation took me 45 minutes to complete, measuring rooms, checking insulation, counting windows. Any contractor skipping this step is just guessing at what size you need.

Installation Procedures (Another half page at least)

• Remove existing Lennox system, including indoor coil
• Install new refrigerant lines (⅜” liquid, ⅞” suction)
• Nitrogen purge during brazing
• Vacuum to 500 microns, hold test for 30 minutes
• Add refrigerant per manufacturer superheat/subcool charts
• Install new disconnect box with surge protector
• Replace 25-year-old thermostat wire (5-wire to 8-wire)
• Install overflow safety switch with float
• Check static pressure, document readings

Every one of these items costs money and takes time. Contractors who don’t list them probably aren’t planning to do them. That nitrogen purge? Prevents contamination that kills compressors three years down the road. The vacuum test? Ensures no moisture in the system. Skip these steps and you’ve got problems coming.

Testing and Commissioning

• Verify refrigerant charge using digital gauges
• Measure temperature split (supply vs return)
• Check amp draw on all motors
• Test all safety controls
• Measure static pressure across coil and filter
• Complete startup checklist (copy provided)

Permits and Compliance

• City of Plano mechanical permit: $187
• Inspection scheduling included
• Load calculation on file for inspection

If there’s no mention of permits, run. Seriously. North Texas cities require permits for HVAC replacements. Frisco, Plano, McKinney – they all have inspectors who check the work. No permit means no inspection, which usually means corners cut. Plus, your homeowner’s insurance can deny claims on non-permitted work.

Red Flags That Should Make You Walk Away

After 15 years in North Texas HVAC, I can spot a sketchy proposal from across the room. Here are the ones that make my blood pressure spike:

“Standard Installation” with no details What’s standard? Their standard? Industry standard? The bare minimum to get it running? I’ve seen “standard” installations with linesets draped across roofs, thermostats mounted crooked, and condensers sitting on dirt because a pad cost extra.

Prices that expire in 24 hours This isn’t milk at Kroger. Equipment prices don’t change daily. Any contractor pressuring you with exploding offers is counting on fear, not quality. Good proposals typically stay valid for 30 days minimum.

“Upgrade to a bigger unit for just $500 more” Oversizing is the fastest way to destroy comfort and efficiency. Your 2,000 square foot house needs about 3 tons of cooling in North Texas, maybe 3.5 if you’ve got single-pane windows and no insulation. That 5-ton unit they’re pushing? It’ll cool too fast, shut off before removing humidity, and leave you with a cold, clammy house. I fix these every summer.

No breakdown between equipment and labor How much is the actual AC unit versus installation? Good contractors separate these costs. If it’s just one lump sum, how do you know you’re not paying $8,000 in labor for a $4,000 system?

“Includes all necessary materials” Which materials? Copper linesets? Condensate pump? Electrical disconnect? Thermostat? Pad? This vague language means they’ll nickel-and-dime you later. “Oh, you want the condensate pump that prevents flooding? That’s extra.”

Missing permit costs In Plano, a mechanical permit runs about $187. Frisco’s similar. If there’s no line item for permits, they’re either skipping them (illegal) or burying the cost elsewhere (dishonest).

“Verbal warranty” If it’s not written, it doesn’t exist. Period. I don’t care how nice Bob seems or how long he’s been in business. When that compressor fails in year three, Bob’s verbal promise won’t fix it.

Questions That Make Bad Contractors Squirm

Want to watch a sketchy contractor’s smile fade? Ask these questions:

“Can you show me the Manual J load calculation?” If they don’t know what this is or say it’s unnecessary, leave. This calculation determines exactly what size system your house needs based on square footage, insulation, windows, and orientation. Guessing at tonnage is malpractice in my book.

“What’s your micron level target for the vacuum?” Should be 500 microns or lower, held for at least 15-30 minutes. If they look confused or say they don’t need to pull a vacuum on a new install, they’re about to destroy your compressor with moisture contamination.

“Are you pulling a new thermostat wire?” Modern systems need more wires than old ones. Your 30-year-old 4-wire setup won’t handle a variable-speed system that needs 8 wires. If they’re planning to “make it work” with the old wire, you’ll have problems.

“What happens if the inspector fails the installation?” Good contractors say “We fix it at no charge and reschedule inspection.” Bad ones blame the inspector or mention additional charges.

“Can you provide three recent references for similar installations?” Not testimonials on their website. Real phone numbers for people whose systems they installed in the last six months. Call them. Ask about the installation process, follow-up, and if the proposal matched the final bill.

“What’s the static pressure specification for this system?” Most residential systems need to stay under 0.5” W.C. total external static pressure. If they don’t measure this, they don’t know if your ductwork can handle the new system. I’ve seen beautiful new systems strangled by undersized ducts, running constantly but barely cooling.

North Texas Makes Everything Harder

Let me tell you why comparing proposals here is trickier than other places. Our heat isn’t just hot – it’s brutal from May through October. Your AC runs 3,000+ hours per year here, compared to maybe 1,500 hours in Ohio. That means every shortcut, every corner cut, shows up fast.

Take refrigerant charge. In moderate climates, you can be off by 10% and nobody notices. Here? Being 10% low on refrigerant when it’s 105°F outside means your system runs all day and never catches up. The compressor overheats, the electric bill explodes, and three years later you need another new system.

Ductwork’s another killer. These 1970s and 1980s homes in Richardson and Plano often have 6” flex ducts where we need 8” or 10” now. Modern high-efficiency systems need more airflow. If the proposal doesn’t mention duct modifications or at least duct testing, they’re assuming your 40-year-old ductwork is perfect. Spoiler: it’s not.

Permits in North Texas aren’t suggestions either. Frisco requires inspections within 24 hours of installation. Plano wants to see that Manual J calculation. McKinney inspectors check refrigerant charge procedures. Skip permits and you might save $200 today, but when you sell your house and the buyer’s inspector finds unpermitted work, you’ll spend thousands fixing it or crediting the buyer.

Then there’s our soil. That black clay expands and contracts like crazy with moisture changes. Condensers need proper pads, not just dirt or gravel. I’ve seen units sink 6 inches in one summer because somebody saved $50 on a proper pad. Now the refrigerant lines are stressed, the unit’s not level, and the compressor’s working twice as hard.

Side-by-Side Proposal Comparison That Actually Works

When the Nguyens in Allen got five proposals last spring, they made a spreadsheet. Smart, but they were comparing wrong things. They had columns for “price” and “warranty” and “brand.” Here’s what actually matters:

Equipment efficiency vs. runtime hours A 14 SEER unit costs $1,000 less than 16 SEER. But running 3,000 hours annually in North Texas? That 16 SEER saves you $180-220 per year. Five years in, you’re ahead.

Installation procedures vs. long-term problems Contractor A includes nitrogen purging, vacuum testing, and new linesets: $8,500 Contractor B reuses linesets, no nitrogen purge: $6,900 That $1,600 difference? Contractor B’s system fails in year 4 from contamination. New compressor: $3,200.

Permit costs vs. future headaches The $187 permit isn’t just paperwork. It’s an inspector checking that the installation meets code. No permit means no inspection means problems hide until they’re expensive.

Labor warranty terms One year? Two years? What’s covered? I’ve seen “comprehensive labor warranties” that exclude refrigerant leaks, electrical issues, and ductwork. That’s not comprehensive; that’s useless.

Company stability markers How long at their current address? Do they have a physical location or just a PO box? Check the Texas Department of Licensing and Regulation for their TACLA license. Expired? Run. No license? Call the cops.

When to Run (Don’t Walk) Away

Some proposals aren’t just bad – they’re dangerous. Leave immediately if:

They want full payment upfront Standard is 50% down maximum, balance on completion. Full payment upfront means they’re using your money to finish the last guy’s job.

“I can start right now if you sign today” Good contractors in July are booked out at least a week. Somebody available immediately in peak season is either desperate or incompetent. Usually both.

Cash-only discounts over 3% Credit cards cost businesses about 3%. A 20% cash discount? They’re not reporting the income. No paper trail means no recourse when things go wrong.

No physical business address Google their address. Is it a warehouse? An actual shop? Or an apartment complex? Legitimate contractors have legitimate locations.

Refuses to put change orders in writing “We’ll figure it out as we go” translates to “I’ll charge whatever I want later.”

Uses your insurance claim as the proposal After hail damage or storms, vultures show up offering to handle your insurance claim. They charge whatever insurance pays, regardless of actual work needed. Your deductible becomes their down payment. Two months later, they’re gone with your money.

The Proposal That Saved the Johnsons $6,000

Last month, Linda Johnson in Frisco called me for a second opinion. Another company had proposed a complete system replacement for $12,000 because her 7-year-old Trane was “inefficient and outdated.” Their proposal was two paragraphs on letterhead.

I spent an hour testing her system. The problem? A failed capacitor ($195) and a refrigerant leak at a service valve ($440 to repair). Her system had another easy 8 years left. The original proposal never mentioned attempting repairs – just straight to replacement.

The worst part? The “new” system they were pushing was actually lower efficiency than her current Trane. They were literally trying to sell her a downgrade for twelve grand.

She called them back to ask why they didn’t mention repair options. They said her system was “too old to waste money fixing.” Seven years old. In North Texas, that’s barely middle-aged for a quality system.

What’s Your Proposal Horror Story?

I’ve shown you what to look for, what to avoid, and what to run from. But every homeowner’s got that one contractor story that makes other people gasp. Maybe it’s the guy who installed your condenser backwards (yes, that happens). Or the company that charged you for permits they never pulled.

If you’re staring at proposals right now trying to figure out who to trust with your home comfort, give us a call at (940) 390-5676. We’ll write you a proposal so detailed it might cure your insomnia, but at least you’ll know exactly what you’re getting. Our proposals typically run 4-5 pages because we spell out everything – from the color of wire nuts we use to the torque specs on electrical connections.

What questions do you still have about reading proposals? Or better yet – what red flag did I miss that burned you?