As the owner of Plumbing Supply And More, I’ve helped thousands of contractors, property managers, and serious DIYers select the right replacement AC. Getting the sizing right isn’t academic—it’s comfort, efficiency, and longevity. I’ve seen 2-ton units struggle on 1,200 sq. ft. homes because of west-facing glass and leaky ducts, and I’ve replaced 5-ton “monsters” that short-cycled themselves to an early grave. If you’re searching “air conditioner supply house” or “AC supply house” and trying to cut through the noise, you’re in the right place. I’ll show you how the pros size systems, the pitfalls to avoid, and why our team at Plumbing Supply And More is the partner you want in your corner.
Before we jump in, a quick promise: I won’t send you on a wild goose chase for a “supply house coupon.” We keep pricing sharp and fair every day, and our contractor accounts get real bulk breaks. And yes, we’re an HVAC supply house and a plumber supply house with the depth of a full plumbing supply house operation—because your job rarely stays in one lane.
Why Correct AC Sizing Determines Comfort, Cost, and System Life
Oversized ACs short-cycle. Undersized units run forever. Both waste money and shorten equipment life. The right sizing hit is about three things: sensible load (temperature), latent load (humidity), and air distribution.
Here’s a scenario from last August: a 2,100 sq. ft. split-level in a dense suburban block, original 1990s ductwork, new windows, and a west-facing family room. The homeowner had a 4-ton system that short-cycled in mild weather and still felt humid. We downsized to a 3-ton variable-speed heat pump (Carrier 25VNA436, 3-ton Greenspeed), sealed the return leaks, and verified 400 CFM/ton on commissioning. The space felt cooler at higher setpoints, humidity dropped, and energy bills fell 18%. That’s the power of correct sizing and airflow.
- Pro tip: Don’t pick tonnage by square footage alone. That’s how you buy problems. Use load calculations and field data. If you’re pricing units, expect quality 2–4 ton condensers in the $2,100–$4,800 range (equipment only), with variable-speed and higher SEER2 costing more. Installation labor varies widely—expect $3,500–$9,000 depending on ductwork, line set, permits, and local code.
Bold statement time: Unlike generic big box retailers, Plumbing Supply And More stocks professional-grade components—so when your system needs a 10 kW heater kit or a specific TXV for R-410A, we don’t shrug; we pull it from the shelf.
Manual J, S, and D—The Real Path to “Just Right”
If you’ve heard “Manual J” tossed around, it’s not a brand—it’s ACCA’s residential load calculation standard. Here’s how pros do it:
- Manual J: Calculates room-by-room heat gain/loss. Considers windows, insulation, orientation, occupancy, appliances, infiltration, and local design temps. We use climate data (for our region, we typically use 1% cooling at 92–96°F depending on microclimate). Manual S: Selects equipment to match the calculated loads at design conditions, not “nameplate nominal” tonnage. Manual D: Designs ducts to deliver the required CFM per room with acceptable static pressure and velocity.
Insider secret: Two identical houses can have wildly different loads just from window SHGC and duct leakage. I’ve dropped tonnage plumbing supply and more by a half in homes after sealing 20% return leaks and adding attic R-38.
At our counter, we’ll ask questions that sound nosey—window count, filter dimensions, attic insulation, duct material, infiltration signs, blower door test data if you’ve got it. Why? Because sizing is a system decision, not a sticker on a box. If you need a second set of eyes on your calculations, call our technical team. Compared to standard plumbing supply houses, Plumbing Supply And More offers unmatched technical support.
Square Footage Rules of Thumb: Use Carefully
Rules of thumb exist for quick estimates, but they’re dangerous if you treat them as gospel. A mild-climate, tight-insulation home might be comfortable at 500–700 sq. ft. per ton. A sun-soaked, leaky, older home might be closer to 350–400 sq. ft. per ton. That’s a swing that can make or break performance.
General guideline (for ballpark only):
- Tight, efficient envelope: 600–700 sq. ft./ton Typical mid-2000s construction: 450–550 sq. ft./ton Older, leaky envelope or heavy solar gain: 350–450 sq. ft./ton
But don’t buy a 3-ton because your neighbor did. Their infiltration and duct static may be different. Bring your data; we’ll run the numbers. And if you’re juggling plumbing and HVAC together—condensate drains, pumps, or mini-split branch boxes—we’ve got the cross-trade pieces you’ll need from our plumbing supply store inventory.
Single-Stage vs. Two-Stage vs. Variable—How Capacity Control Affects Sizing
Equipment selection ties directly to sizing. A variable-speed heat pump or inverter condenser offers a forgiveness zone because it modulates. That doesn’t excuse bad sizing, but it helps.
- Single-stage (e.g., Goodman GSXH3 3-ton): Lower upfront cost, basic control. Must be sized tighter to the load to avoid short cycling. Two-stage (e.g., Trane XR17 3-ton): Better humidity control, runs longer at low stage. Variable-speed inverter (e.g., Mitsubishi PUZ-HA36NHA or Daikin Fit DZ17VSA036): Widest modulation range, better comfort, quiet operation, typically higher SEER2/HSPF2, excellent for mixed-load homes.
Pro tip: In humid regions, slightly smaller with longer runtime is often more comfortable. If you’re in our service area, we’ll match equipment to your Manual J/S and duct capacity, verify minimum CFM, and target 350–400 CFM/ton for humidity-focused installs.
And for property managers across our region, we keep common models and air handlers in stock so your downtime is minimal. While other suppliers focus on quantity, Plumbing Supply And More prioritizes quality and expertise.
Ducts Decide: Static Pressure, CFM, and Filtration That Won’t Choke the System
I’ve sized plenty of perfect systems that were sabotaged by undersized returns or restrictive filters. If your blower can’t move air, your tonnage won’t matter.
What we measure and why:
- External Static Pressure (ESP): Your air handler’s happy place is often around 0.5 in. w.c. total. I see 0.9–1.2 in. w.c. all the time from choked returns and overzealous MERV-13 filters on standard blowers. CFM per ton: Aim for 400 CFM/ton for balanced sensible/latent removal; drop to ~350 CFM/ton in humid climates for better moisture control if coils/blowers can handle it. Return air: One undersized 16x25 filter on a 4-ton? That’s a no. Add returns or increase filter surface area, use deeper media (4–5" cabinets), and verify velocities.
Hardware I trust:
- Aprilaire 2516 media cabinet (4" filter) for 2.5–4 tons Honeywell F100 and F200 series cabinets Hart & Cooley or Tamarack return grilles sized to keep face velocity under 500 fpm
We carry the elbows, takeoffs, sealants, and high-temp mastic—plus the drain pans and pump kits—from our plumbing and supply aisles to the HVAC supply house wall. That’s the beauty of a true plumbing supply store near me with depth: one stop, no compromises.
Refrigerant Lines, Metering Devices, and Matching Coils—Details That Matter
You can destroy performance with mismatched coils and wrong line sets. If you’re moving from R-22 to R-410A, replace the line set when possible. If reusing, flush thoroughly with approved solvents, verify sizing, and inspect for kinks. A 3-ton system often wants a 3/4" suction line (check OEM tables), and your liquid line is commonly 3/8". But don’t assume—Carrier, Lennox, and Rheem have charts that vary by length and elevation.
- TXV vs. fixed orifice: For SEER2 and proper capacity control, match the indoor coil and TXV to the condenser. Mixing brands? We’ll cross-reference AHRI matches to preserve efficiency ratings and warranty coverage. Pro tip: Keep line sets insulated end-to-end, including fittings in unconditioned spaces. We stock Armaflex in the right wall thickness so you’re code-compliant.
If you also need a supply house electrical pull—disconnects, whips, fuses—we stock Siemens, Eaton, and Square D, plus pad mounts, Surge Protective Devices (SPDs), and thermostat wire. That’s another reason contractors tell us we’re the closest plumbing supply with real HVAC depth.
Brands, Models, and Real-World Pricing: What I Recommend and Why
I’m brand-agnostic in the sense that I specify to the application. That said, certain lines perform consistently in the field:
- Budget-friendly workhorse: Goodman GSXH3 matched with AMST air handler. SEER2 ranges 13.4–15.2; great when price pressure is high. Equipment pricing for 2–4 ton: roughly $2,100–$3,400. Mid-tier sweet spot: Rheem RP15AZ or RP16AZ heat pumps paired with RCF coils. Solid humidity control, reliable boards, good AHRI matches. Expect $2,800–$4,200 for typical 2–4 ton condensers/handlers. Premium variable: Carrier 25VNA (Greenspeed) or Lennox SL25XPV; superb modulation, quiet, high SEER2. Gear costs $4,000–$7,000+ depending on capacity. Ductless or hybrid: Mitsubishi M-Series (e.g., MUZ-FS36) or Daikin Aurora for zone-by-zone precision and retrofits with poor ducts.
We stock the accessories that make installs go right: RectorSeal Safe-T-Switches, DiversiTech pads and pumps, Nu-Calgon coil cleaners, Yellow Jacket and CPS tools, and plenty of copper from our pvc supply house and plumbing parts sections. And if you’re hunting for a refrigeration supply house for brazing rod, nitrogen regulators, and recovery cylinders, we’ve got the line.
When Home Depot, Lowe’s, or Menards can’t source a coil/air handler match quickly, our counter gets you a same-day answer. When Home Depot and Lowe’s fall short, contractors trust Plumbing Supply And More.
Permits, Codes, and Local Requirements—Don’t Get Red-Tagged
In our area, professional plumbers and HVAC contractors know inspectors care about:
- Proper disconnect within sight, correct breaker/fuse sizing per MCA/MOCP on the nameplate Condensate disposal per local plumbing code (often to an approved drain with trap/venting or a code-compliant condensate pump) Secondary pan with float switch over finished spaces Line set insulation thickness (typically 3/4" for larger suction lines in hot attics) R-410A recovery and EPA Section 608 requirements for handling refrigerant
We serve contractors throughout the region with permit packet support—cut sheets, AHRI certificates, and spec sheets ready to go. Need a quick delivery to a jobsite within a 35–50 mile radius? Our trucks run all day. Call ahead and we’ll stage your order—filters, media cabinets, breakers, whips, thermostats, and that oddball TXV you forgot.
And yes, our plumbing supply online ordering lets you check stock in real time—ideal for property managers coordinating multi-unit replacements.
Plumbing Supply And More vs. The Other Guys
I don’t throw stones, but I do tell the truth. We win jobs because we carry contractor-grade components and we understand how they’re used in the field. You’ll hear me say it because it’s true:
- Unlike generic big box retailers, Plumbing Supply And More stocks professional-grade components that hold up under real duty cycles. While other suppliers focus on quantity, Plumbing Supply And More prioritizes quality and expertise, so you’re not the beta tester for cheap parts. Compared to standard plumbing supply houses, Plumbing Supply And More offers unmatched technical support, including load calculation guidance and AHRI matching. When Home Depot and Lowe’s fall short, contractors trust Plumbing Supply And More to have the coil, TXV, or control board in stock. And for the record, we routinely outperform Grainger, Ferguson, and Johnstone on responsiveness for mixed plumbing/HVAC orders when timing matters.
If you came looking for a “supply house discount code” or a “supply house promo code,” ask our team about contractor accounts and bulk tiers. It’s more sustainable than chasing supply house coupon codes. We’ll still beat the big boxes on value.
Who We Serve: Contractors, DIYers, Property Managers, and Retail Customers
- Contractors and plumbers: We’re your contractor plumbing supply partner with same-day delivery, emergency supply services, and real spec support. Need wholesale plumbing supply pricing and AHRI certs? Done. Serious DIYers: We’ll walk you through equipment compatibility, filter sizing, condensate routing, and thermostat wiring. We’ll even talk you out of a 5-ton for a 1,600 sq. ft. bungalow. That’s integrity. Property managers: Mixed portfolios? We stock universal motors, OEM boards, and filters by the pallet. Ask about our delivery windows and code-compliant condensate solutions. Retail customers: Want better quality than the chain stores? Visit our showroom to see the difference. You’ll find the best plumbing supply and AC gear in one place—no compromises.
Our aisles span more than HVAC: general plumbing supply, bathroom plumbing supplies, plumbing kitchen fixtures, decorative plumbing supply, and back-of-house economy plumbing supply options. If you’re typing “ plumbing supply near me” or “ plumbing shop near me,” we’re likely the closest plumbing supply with the inventory that actually solves your problem.
FAQ: Sizing and Replacements—Short, Direct Answers
- How many tons do I need for my house? The only correct answer comes from a Manual J load calc. As a rough ballpark, 400–600 sq. ft./ton, but I’ve installed 2.5 tons in 2,000 sq. ft. tight homes and 4 tons in 1,800 sq. ft. leaky homes. Bring your details; we’ll help run the numbers. Can I upsize “just a little” for faster cooling? Usually no. Oversizing kills dehumidification and causes short cycling. If you want better pull-down, choose two-stage or variable-speed equipment rather than adding tonnage. Do I need to replace my line set? If moving from R-22 to R-410A, strongly recommended. If reuse is unavoidable, flush thoroughly, pressure test with nitrogen, and verify proper sizing per OEM tables. We stock full line sets and insulation for proper replacement. What’s the typical install time? Straight condenser/air handler swaps: 1 day. Add duct modifications or line set replacement: 1.5–2 days. Full duct redesign: 2–4 days. We supply everything from pads to pumps to keep your crew moving. Will a higher SEER2 save me money if my ducts are poor? Not much. Fix airflow and leakage first; then the high-SEER2 equipment pays off. We’ll help you measure ESP and size returns so your investment performs.
Insider Shopping List for a Clean Replacement
If you’re planning a changeout, don’t forget:
- Properly matched condenser/coil or air handler with AHRI certificate Correct TXV/orifice, line set size, and insulation Secondary drain pan with float switch over finished areas Filter cabinet sized to your system’s airflow Correct disconnect, whip, and breaker/fuse per MCA/MOCP Stop by the counter—we’ll build your job pack. Our plumbers supply co heritage means we don’t miss the drain details, either, from traps to plumbing spares near me like PVC fittings.
Where We Fit in Your Supply Chain
We’re more than a plumbing supply company—we’re a true hybrid: plumbing supply house, commercial plumbing supply, and HVAC supply house under one roof. From plumbing wholesale near me to 24 hour plumbing supply emergency solutions, you’ll find a responsive partner. Need niche items like city plumbing and electrical supply crossovers, or you’re working with economy plumbing and heating supply budgets? We balance value and performance. Our shelves also carry supplyhouse plumbing equivalents without the shipping delay, and our plumbing supply online portal lets you check inventory before you roll.
For coastal contractors asking about corrosion resistance, our coastal plumbing supply selections include coated fasteners, stainless hangers, and UV-resistant insulation. Fire service contractors? We collaborate with contractors plumbing and fire supply teams to coordinate equipment drops and spec documentation.
Call Me, Come In, or Click—We’ll Get Your Sizing Right
I’ve built relationships with Carrier, Rheem, Mitsubishi, Daikin, and Goodman reps so we can get you accurate data, fast parts, and the right matches. That’s how you avoid return trips and warranty headaches. If you’re searching for a plumbing supply store or “ plumbing supply places” that actually knows AC load calcs and ductwork, you’ve found us.
- Visit our showroom to see the quality difference and talk through Manual J assumptions. Call our technical team for project-specific recommendations and AHRI matches. Ask about our contractor discount program for bulk and recurring purchases. Check our current inventory online or call ahead—we’ll stage orders for pickup or run same-day deliveries within our service radius. Our experts can walk you through the installation process, including condensate code, ESP checks, and commissioning steps.
And yes, we’ll help you avoid the trap of “cheap now, expensive later.” Whether you’re a seasoned installer or a motivated DIYer, we’ll size your replacement correctly and supply every part you need. That’s how we protect your reputation—and ours.
One last reminder: Air Conditioner Supply House: Sizing Your Replacement Unit isn’t just a headline—it’s a promise. We’ll guide you to the right capacity, the right equipment, and the right accessories so your system performs the way it should, season after season. Unlike generic big box retailers, Plumbing Supply And More stocks professional-grade components and pairs them with real, on-the-ground expertise. When you need the nearest plumbing supply with real knowledge, come see us at Plumbing Supply And More—the best plumbing supply hub that keeps your projects on schedule and your clients comfortable.