Air Conditioning Guides & Calculators
63 expert guides covering central AC, mini splits, portable units, sizing calculators, and more
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AC Sizing & Selection
BTU calculators and sizing guides for proper AC selection
5,000 BTU Air Conditioner: What Room Size Can It Cool? (2026)
A 5,000 BTU air conditioner cools 100–250 sq ft depending on conditions. Learn the exact room sizes, best uses, top models, and when you need to size up to 6,000 or 8,000 BTU.
What Size AC for 1,000 Sq Ft? (BTU & Tonnage Guide 2026)
A 1,000 sq ft home needs 1.5–2.5 tons (18,000–30,000 BTU) of air conditioning depending on climate and insulation. Complete sizing guide with data tables, examples, and equipment recommendations.
What Size AC for 1,500 Sq Ft? (BTU & Tonnage Guide 2026)
A 1,500 sq ft home needs 2–3.5 tons (24,000–42,000 BTU) of air conditioning. Complete sizing data by climate zone, insulation, and home type with cost estimates and equipment picks.
What Size AC for 2,000 Sq Ft? (BTU & Tonnage Guide 2026)
A 2,000 sq ft home needs 2.5–4 tons (30,000–48,000 BTU) of air conditioning. Complete sizing guide with data tables for every climate zone, adjustment factors, and cost comparisons.
What Size AC for 2,500 Sq Ft? (BTU & Tonnage Guide 2026)
A 2,500 sq ft home needs 3–5 tons (36,000–60,000 BTU) of air conditioning. Covers single vs dual system sizing, zoning options, and equipment costs for every climate zone.
What Size AC for 3,000 Sq Ft? (BTU & Tonnage Guide 2026)
A 3,000 sq ft home needs 4–6+ tons (48,000–72,000 BTU) of air conditioning — usually requiring two systems. Complete sizing guide with single vs dual system analysis, zoning, and costs.
What Size AC for 500 Sq Ft? (Studio & Small Room Cooling 2026)
A 500 sq ft studio or room needs 10,000–14,000 BTU (about 1 ton) of air conditioning. Covers window AC vs mini split vs portable options, costs, and sizing adjustments for studios, bedrooms, and offices.
AC Tonnage Calculator Per Square Foot (+Sizing Chart) 2026
Calculate the exact AC tonnage for your home by square footage. Includes a complete tonnage-per-square-foot chart for all home sizes (500–5,000 sq ft), climate zones, and tonnage conversion tables.
Air Conditioner BTU Calculator: What Size AC Do You Need? (2026)
Use our free BTU calculator to find the exact air conditioner size for your room or home. Covers square footage, climate zones, insulation, ceiling height, and 12+ adjustment factors for accurate AC sizing.
Furnace Size Calculator: What Size Furnace Do I Need? (2026)
Calculate the right furnace size (BTU) for your home based on square footage, climate zone, insulation, and 10+ factors. Includes BTU sizing charts for every home size and tips to avoid costly oversizing.
Heat Pump Size Calculator: What Size Heat Pump Do I Need? (2026)
Calculate the right heat pump size for your home. Covers sizing for both heating and cooling, cold-climate heat pumps, auxiliary heat requirements, and tonnage charts by square footage and climate zone.
How Many BTU Per Square Foot for Heating & Cooling? (2026 Guide)
Learn the exact BTU per square foot you need for both heating and cooling. Covers all 7 DOE climate zones, insulation levels, and building types with detailed charts and adjustment factors.
How Many Mini Splits Do I Need? (Rooms, Zones, BTUs) 2026
Calculate how many mini split indoor heads you need based on rooms, zones, and BTU loads. Covers whole-home systems, supplemental cooling, multi-zone vs single-zone, and layout strategies for every home size.
Is It OK To Oversize A Mini Split? (Oversizing Problems Explained) 2026
Oversizing a mini split by more than 25% causes short cycling, poor humidity control, and wasted money. Learn exactly how much oversizing is acceptable, the problems it causes, and how to fix an oversized unit.
Mini Split Sizing Calculator: What BTU Mini Split Do I Need? (2026)
Calculate the exact mini split size for any room or zone. Covers single-zone and multi-zone sizing, garage and sunroom applications, and the complete BTU sizing chart for all common room sizes.
Water Heater Sizing Calculator: Tank vs Tankless Sizing (2026)
Calculate the right water heater size for your household. Compare tank (30–80 gallon) vs tankless (GPM) sizing, first-hour ratings, recovery rates, and get recommendations by household size.
What Size Generator Do I Need? Appliance Wattage Calculator (2026)
Calculate the exact generator size for your home, RV, or job site. Covers starting vs running watts for AC units, furnaces, refrigerators, sump pumps, and 40+ appliances with our free wattage calculator.
What Size Mini Split for a Garage? (1-Car, 2-Car, 3-Car Guide 2026)
Find the exact mini split BTU size for your garage: 1-car (9,000–12,000 BTU), 2-car (18,000–24,000 BTU), 3-car (24,000–36,000 BTU). Covers insulated vs uninsulated, workshops, and heating.
What Size Tankless Water Heater Do I Need? (2026 Sizing Guide)
Calculate the right tankless water heater size based on flow rate (GPM), temperature rise, and simultaneous fixtures. Covers gas vs electric, whole-home vs point-of-use, and climate zone adjustments.
Mini Split Systems
Ductless AC systems, multi-zone setups, and installation guides
AC Dry Mode vs Dehumidifier: Which Removes More Humidity?
Head-to-head comparison of mini split dry mode vs standalone dehumidifier — moisture removal rates, energy use, cost, and when to use each.
Best 2-Zone Mini Split Systems in 2026
Top 2-zone mini split systems for heating and cooling two rooms. Sizing configurations, brand comparisons, and installed cost breakdowns.
Best 3-Zone Mini Split Systems in 2026
Top 3-zone mini split systems ranked by efficiency, noise, and value. Sizing guide, installation costs, and brand comparisons for 3-room setups.
Best 4-Zone Mini Split Systems in 2026
Top 4-zone mini split systems compared by specs, efficiency, and price. Sizing guide for 4-room configurations with installation cost breakdowns.
Best 5-Zone Mini Split Systems in 2026
The top 5-zone mini split systems for whole-home heating and cooling. Mitsubishi, Daikin, Fujitsu, and MrCool compared with sizing examples.
Best DIY Mini Splits: Easiest to Install Yourself (2026)
The top DIY mini split systems ranked by ease of installation, efficiency, and value. MrCool, Senville, Pioneer, and Cooper&Hunter compared with real install data.
Best Mini Split AC Units in 2026 (Specs-Based Rankings)
The top mini split AC units in 2026 ranked by efficiency, noise, reliability, and value. AHRI-certified specs, not paid placements. Covers single-zone and multi-zone.
Best Mini Split for Garage (1-Car, 2-Car, 3-Car Sizing Guide)
How to size and choose a mini split for your garage — BTU requirements by garage size, insulation factors, top picks, and installation tips.
Best Cassette Ceiling Air Conditioners (Specs + Installation Guide)
Ceiling cassette mini split guide — how they work, sizing, top models from Mitsubishi, Daikin, Fujitsu, installation requirements, and cost breakdown.
Daikin Mini Split Reviews: Premium AC Deep-Dive (2026)
Complete Daikin mini split review covering Aurora, Emura, Fit, and Quaternity series. Specs, pricing, warranty details, and who should buy Daikin.
AC Dry Mode Explained: What It Does & When to Use It
What dry mode does on your mini split or AC, how it differs from cool mode, when to use it, and how much energy it saves. Plus humidity comfort guidelines.
How Does a Mini Split Work? (7-Step Explanation)
A step-by-step explanation of how mini split air conditioners work — the refrigeration cycle, inverter technology, heating mode, and defrost operation explained simply.
How Much Does It Cost to Run a Mini Split? (Monthly Calculator)
Calculate your mini split's monthly and annual running cost with real electricity rates by state. Includes cost breakdowns for 9K–36K units in cooling and heating mode.
Mini Split Air Conditioners: Complete Guide (2026)
Everything you need to know about mini split air conditioners — how they work, what they cost, top brands, sizing, installation, and whether a ductless system is right for your home in 2026.
Mini Split Brands Ranked: Mitsubishi vs Daikin vs MrCool vs Senville (2026)
Data-driven comparison of every major mini split brand — Mitsubishi, Daikin, Fujitsu, MrCool, LG, Senville, Carrier, and more. Specs, reliability, warranty, and value ranked.
How Much Electricity Does a Mini Split Use? (Watts, kWh, Amps)
Real electricity consumption data for mini splits by size — wattage, kWh per day/month/year, and how usage compares to central air, window units, and space heaters.
Best Mini Split for Bedroom (Quiet, Efficient, Right-Sized)
Find the perfect bedroom mini split — noise levels compared, BTU sizing for bedrooms, sleep mode features, and top picks from Mitsubishi, Daikin, Fujitsu, and MrCool.
Mini Split Installation Cost: What to Expect (2026 Prices)
Complete breakdown of mini split installation costs — labor, materials, electrical, permits. Single-zone, multi-zone, DIY vs professional pricing with real contractor quotes.
Best Mini Split Line Set Cover Kits (DIY Installation Guide)
Top line set cover kits for mini splits — PVC, paintable, and decorative options. Sizing, installation steps, and which covers fit MrCool, Senville, and more.
Mini Split Maintenance: Cleaning, Filters, and Annual Service Guide
Complete mini split maintenance schedule — filter cleaning, coil cleaning, drain clearing, and when to call a pro. Step-by-step with photos and timing.
Mini Split vs Central Air: Which Is Better? (8 Key Differences)
Side-by-side comparison of mini split vs central air on cost, efficiency, installation, noise, aesthetics, maintenance, resale value, and zone control. Data-driven guide.
MrCool 3rd Gen vs 4th Gen: Which DIY Mini Split to Buy?
Detailed spec comparison of MrCool DIY 3rd Gen vs 4th Gen — efficiency, noise, cold-climate performance, price, and which is the better buy in 2026.
MrCool DIY Mini Split Review: Honest Pros & Cons (2026)
In-depth MrCool DIY mini split review covering 3rd Gen and 4th Gen models. Real specs, installation experience, reliability data, and who should (and shouldn't) buy one.
Senville Mini Split Reviews: Complete Brand Analysis (2026)
Honest Senville mini split review — SENL and AURA series specs, real-world performance, reliability concerns, and who should buy Senville vs alternatives.
Smallest Mini Split ACs (Under 10,000 BTU) — 2026 Guide
The smallest mini split air conditioners for small rooms, offices, and server closets. 6K and 9K BTU models compared by size, noise, and efficiency.
What Is a Mini Split AC? How Ductless Systems Work
A clear, beginner-friendly explanation of what a mini split air conditioner is, how it differs from central air and window units, key components, and who should consider one.
Portable Air Conditioners
Portable and window AC units for targeted cooling
Best Dual-Hose Portable ACs (More Efficient Cooling)
The top dual-hose portable air conditioners for 2026. More efficient, faster cooling, and no negative pressure — complete specs, pricing, and expert picks.
Best Portable AC for Apartments (Studio, 1-Bed, 2-Bed)
The best portable air conditioners for every apartment size in 2026. Sizing guides, noise considerations, and top picks for studios, 1-bedrooms, and 2-bedrooms.
Best Portable AC & Heater Combos (2-in-1 Year-Round)
Top portable AC and heater combination units for 2026. Year-round cooling and heating in one unit with BTU specs, efficiency data, and cost analysis.
Best Portable ACs in 2026 (Ranked by Energy Efficiency)
The top portable air conditioners of 2026 ranked by CEER efficiency ratings. Real-world testing data, electricity costs, noise levels, and BTU comparisons for every budget.
Biggest Portable ACs for Large Rooms (14,000+ BTU)
The most powerful portable air conditioners for large rooms in 2026. 14,000+ DOE BTU units ranked by cooling capacity, efficiency, and real-world performance in 450–700+ sq ft spaces.
Can You Use a Portable AC Without the Hose? (4 Options)
Find out if you can run a portable air conditioner without the exhaust hose. Explains why cooling mode won't work, plus 4 alternatives that actually cool without a hose.
Cheapest Portable Air Conditioners in 2026 (Best Budget)
The best budget portable ACs under $350 in 2026. Affordable cooling that actually works — real specs, efficiency data, and honest assessments of where budget units compromise.
Do Portable ACs Pull Air From Outside? (Wildfire Smoke)
Do portable air conditioners bring in outdoor air? Complete explanation for single-hose vs dual-hose units, plus how to protect indoor air quality during wildfire smoke events.
How Do Portable Air Conditioners Work? (Simply Explained)
A clear, visual explanation of how portable air conditioners cool your room. Covers refrigeration cycle, single vs dual-hose airflow, dehumidification, and why venting is required.
How to Drain a Portable AC (+ How Often to Drain)
Complete guide to draining a portable air conditioner. Covers auto-evaporative systems, manual draining, continuous gravity drains, and how often each climate requires drainage.
How to Vent a Portable AC Without a Window (5 Methods)
Five proven methods to vent a portable air conditioner when you don't have a standard window. Step-by-step instructions for sliding doors, drop ceilings, walls, dryer vents, and casement windows.
How Much Electricity Does a Portable AC Use? (Cost Calc)
Calculate exact portable AC electricity costs by BTU size, CEER rating, and your local electric rate. Includes hourly, daily, monthly, and annual cost tables for every scenario.
Portable AC vs Window AC: Which Should You Buy?
Data-driven comparison of portable vs window air conditioners. Efficiency, cost, noise, installation, and cooling performance tested side-by-side with real numbers.
Best Window Seal Kits for Portable ACs (DIY Install)
Top portable AC window seal kits for 2026 ranked by seal quality and ease of install. Covers sliding windows, casement windows, sliding doors, and DIY plexiglass options.
Portable Air Conditioners: Complete Buyer's Guide (2026)
Everything you need to know before buying a portable AC in 2026. BTU sizing, single vs dual-hose, energy costs, noise levels, top picks, and expert tips from HVAC professionals.
Quietest Portable ACs in 2026 (Under 53 dB)
The quietest portable air conditioners ranked by actual noise levels. Decibel comparisons, sleep mode testing, and the best low-noise units for bedrooms and offices.
Single-Hose vs Dual-Hose Portable AC: Which Is Better?
Detailed comparison of single-hose and dual-hose portable air conditioners. Efficiency data, cooling tests, energy costs, and clear recommendations for every situation.
Smallest Portable AC Units (Compact Cooling Solutions)
The most compact and lightweight portable air conditioners in 2026. Units under 50 lbs and 16 inches wide for small rooms, dorms, RVs, and tight spaces.
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AC Tonnage Calculator Per Square Foot (+Sizing Chart) 2026
Calculate the exact AC tonnage for your home by square footage. Includes a complete tonnage-per-square-foot chart for all home sizes (500–5,000 sq ft), climate zones, and tonnage conversion tables.
Air Conditioner BTU Calculator: What Size AC Do You Need? (2026)
Use our free BTU calculator to find the exact air conditioner size for your room or home. Covers square footage, climate zones, insulation, ceiling height, and 12+ adjustment factors for accurate AC sizing.
Furnace Size Calculator: What Size Furnace Do I Need? (2026)
Calculate the right furnace size (BTU) for your home based on square footage, climate zone, insulation, and 10+ factors. Includes BTU sizing charts for every home size and tips to avoid costly oversizing.
Heat Pump Size Calculator: What Size Heat Pump Do I Need? (2026)
Calculate the right heat pump size for your home. Covers sizing for both heating and cooling, cold-climate heat pumps, auxiliary heat requirements, and tonnage charts by square footage and climate zone.
Mini Split Sizing Calculator: What BTU Mini Split Do I Need? (2026)
Calculate the exact mini split size for any room or zone. Covers single-zone and multi-zone sizing, garage and sunroom applications, and the complete BTU sizing chart for all common room sizes.
Best Mini Split AC Units in 2026 (Specs-Based Rankings)
The top mini split AC units in 2026 ranked by efficiency, noise, reliability, and value. AHRI-certified specs, not paid placements. Covers single-zone and multi-zone.