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Is This System the Right Size for Your Home? Matching Goodman’s 3 Ton R-32 + Furnace Package to Real Floorplans

Introduction: Bigger Isn’t Always Better

When homeowners shop HVAC, the most common mistake is thinking “bigger is better.” But oversizing your system is like putting a V8 engine in a lawnmower—it won’t run right.

That’s why sizing is everything. The Goodman 3 Ton 15.2 SEER2 R-32 air conditioner condenser with vertical coil and 100,000 BTU 96% AFUE furnace is a strong package—but is it the right size for your house?

In this guide, we’ll break down:

What “3 tons” of cooling really means.
What 100,000 BTUs of heating covers.
How to account for climate, insulation, and windows.
The role of Manual J load calculations .
Common mistakes when sizing HVAC.
Real-world examples of floorplans where this Goodman package is a perfect fit—and where it isn’t.

What Does 3 Tons of Cooling Really Mean?

“Ton” in HVAC doesn’t mean weight—it means cooling capacity.

1 ton = 12,000 BTUs/hour.
3 tons = 36,000 BTUs/hour.

Rule of thumb (dangerous if used alone):

1 ton per 400–600 sq. ft.
3 tons covers roughly 1,200–1,800 sq. ft.

👉 But square footage is just a starting point. The Department of Energy warns against using rules of thumb alone. Climate, insulation, windows, and ceilings all change the load.

What Does 100,000 BTUs of Heating Cover?

Heating load depends heavily on climate zone.

Mild climates (South): 100k BTUs heats 2,500–3,000 sq. ft.
Moderate climates (Midwest): 2,000–2,400 sq. ft.
Cold climates (North): 1,800–2,200 sq. ft.

This Goodman furnace is a workhorse for medium-to-large homes in cold regions. In the South, it’s often oversized.

👉 Source: DOE Furnaces & Boilers Guide .

The Climate Factor

Your location changes everything.

Hot & humid (Florida, Texas): Cooling load dominates. A 3-ton AC may cover only 1,200–1,400 sq. ft.
Moderate (Virginia, Ohio): 1,500–1,800 sq. ft.
Cold (Minnesota, Maine): Furnace is more critical; AC load smaller. A 3-ton can stretch to 2,000 sq. ft.

Check your climate zone on the Energy Star Climate Map .

Jake’s take: Sizing isn’t “one size fits all.” A 3-ton in Minnesota covers more square footage than the same unit in Texas.

Why Manual J Matters

The gold standard for sizing is the Manual J load calculation from the ACCA (Air Conditioning Contractors of America).

Manual J accounts for:

Square footage.
Insulation levels.
Windows and orientation.
Occupancy.
Infiltration (draftiness).

👉 Quick read: What is Manual J?

Jake’s tip: Don’t trust a contractor who sizes your system by square footage alone. If they won’t do a Manual J, call someone else.

The Danger of Oversizing

Short cycling: Unit turns on/off too often, wasting energy.
Humidity issues: Air conditioner doesn’t run long enough to dehumidify.
Comfort problems: Rooms feel clammy or uneven.
Lifespan reduction: Extra wear-and-tear on compressor and furnace.

👉 Source: Energy Star Sizing Guide .

Jake’s take: Bigger = wasted money, shorter lifespan, worse comfort. Don’t do it.

The Danger of Undersizing

Can’t keep up on hottest or coldest days.
System runs nonstop, driving up bills.
Uneven temps in far rooms.

Jake’s take: Undersized = sweat in July, freeze in January. Neither is fun.

Real-World Floorplan Scenarios

1. 1,500 sq. ft. ranch, Columbus, OH

Cooling load: ~30k BTUs (2.5 tons).
Heating load: ~85k BTUs.
Goodman 3 ton/100k BTU: Slightly oversized, but within safe range. ✅

2. 1,800 sq. ft. two-story, Minneapolis, MN

Cooling load: ~36k BTUs (3 tons).
Heating load: ~95–100k BTUs.
Perfect fit for this Goodman package. ✅

3. 2,200 sq. ft. split-level, Atlanta, GA

Cooling load: ~48k BTUs (4 tons).
Heating load: ~70k BTUs.
AC side undersized. Furnace oversized. ❌

4. 1,400 sq. ft. bungalow, Houston, TX

Cooling load: ~42k BTUs (3.5 tons).
Heating load: ~50k BTUs.
AC undersized. Furnace massively oversized. ❌

Jake’s verdict: This Goodman package shines in the Midwest and North, not the Deep South.

Common Sizing Mistakes

Sizing to square footage only.
Ignoring insulation upgrades.
Not factoring in ceiling height (cathedral ceilings = bigger load).
Forgetting about windows (large south-facing glass = extra load).
Oversizing “just in case.”

👉 DOE backs this up: Air Conditioner Efficiency Tips .

The R-32 Advantage in Sizing

Why does R-32 matter here?

Transfers heat more efficiently than R-410A.
Requires less refrigerant charge.
Allows Goodman to hit 15.2 SEER2 efficiency in a compact 3-ton package.

👉 Source: EPA AIM Act (HFC phase-down ).

Jake’s take: R-32 gives you more cooling per pound of refrigerant—so a 3-ton today outperforms older 3-ton R-410A systems.

The Furnace Side: AFUE + BTUs in Winter

96% AFUE = only 4% wasted.
100k BTUs = plenty for northern winters.

Compare that to an 80% furnace:

Uses 20% more fuel for the same heat.
Costs ~$200–$300 more per year in cold states.
Over 15 years = $3,000–$4,500 wasted.

👉 Energy Star Furnace Guide .

Sizing Your Own Home: A DIY Shortcut

While you need a Manual J for precision, here’s a DIY ballpark:

Cooling load = 20 BTUs per sq. ft. (moderate climates).
Heating load = 40–50 BTUs per sq. ft. (cold climates).

Example: 1,800 sq. ft. Midwest home

Cooling = 1,800 × 20 = 36,000 BTUs (3 tons).
Heating = 1,800 × 50 = 90,000 BTUs (close to 100k).
Goodman system = perfect match.

Jake’s take: Use the formula for ballpark numbers. Use Manual J for the final say.

Rebates & Incentives

This system’s efficiency makes it rebate-eligible:

Federal Tax Credits (2025):
- $600 for high-efficiency AC.
- $600 for furnaces.
- Energy Star Tax Credits .
Utility Rebates: Many providers offer $200–$800 for SEER2/AFUE upgrades.
State Programs: CA, NY, MA add incentives for high-AFUE furnaces.