Heating & cooling, in plain language

Best SEER Rating for Florida's Climate

In Florida's long, cooling-dominated climate, a mid-to-upper efficiency SEER2 system is usually the sweet spot for most homes, and…

Coastal Coil Protection: Coated vs Standard

Salt-laden coastal air corrodes the outdoor condenser coil and shortens equipment life for units near the ocean, often faster than…

Gas Furnace vs Electric Strip Heat

A gas furnace burns a fuel like natural gas or propane in a heat exchanger and blows air across it, making heat from combustion. E…

Heat Pump vs Straight-Cool Air Conditioner

A straight-cool air conditioner only cools, so it needs a separate heat source such as a furnace or electric strip heat to keep th…

SEER and SEER2 Ratings Explained

SEER stands for Seasonal Energy Efficiency Ratio, a measure of how much cooling an air conditioner or heat pump delivers per unit …

SEER2 Upgrade Savings: What Actually Drives the Payoff

SEER2 is the current efficiency rating for air conditioners: the seasonal cooling output divided by the energy used, measured unde…

Single-Stage, Two-Stage, and Variable-Speed Compressors

A single-stage compressor runs at full blast or off, with nothing in between. A two-stage compressor adds a lower gear so it can r…

Auxiliary Heat

Auxiliary heat is the backup heating a heat pump switches on when it cannot pull enough warmth from the outdoor air on its own — a…

Condo Water-Source Heat Pumps: Loop, Tower, Association and Permit

A water-source heat pump in a condo is a heat pump in or beside your unit that trades heat with a loop of water piped through the …

Emergency Heat

Emergency heat — the "EM HEAT" setting on a heat pump thermostat — is a mode you switch on manually that shuts the heat pump off a…

Forced-Air Heating

Forced-air heating is a system that warms air at a central appliance, usually a furnace or a heat pump air handler, and uses a blo…

Geothermal Heating and Cooling

Geothermal heating and cooling uses a ground-source heat pump that exchanges heat with the earth instead of the outdoor air. A bur…

Heat Pump Defrost Mode: What It Is and What Is Normal

Defrost mode is the heat pump's automatic way of melting frost off its outdoor coil while it is heating. For a few minutes the sys…

Heat Pump vs Furnace

A heat pump moves heat and can both heat and cool a home, running on electricity and staying efficient in mild climates. A furnace…

Heat Pumps in Florida, and What Salt Air Does to the Outdoor Unit

A heat pump is an air conditioner that can also run in reverse, so one outdoor unit both cools and heats the house. In Florida, tw…

When to Turn On Your Heat

There is no single calendar date to turn on your heat. The real trigger is when it gets cold enough outside that your home can no …

How a Thermostat Works

A thermostat is essentially a temperature-controlled switch. It measures the temperature of the air around it and, when that readi…

How to Reset a Thermostat

There are three general ways to reset a thermostat: power cycle it by switching the system off at the thermostat and at the breake…

Signs a Thermostat Is Going Bad

The classic signs of a bad thermostat are a blank or unresponsive screen, a system that won't turn on or won't shut off, a room te…

Smart Thermostats: What They Do and Whether One Fits Your System

ENERGY STAR describes a smart thermostat as a Wi-Fi enabled device that automatically adjusts the heating and cooling settings in …

The C-Wire on a Thermostat

The C-wire, or common wire, is the thermostat wire that provides continuous power to the thermostat. Older thermostats did not nee…

Thermostat Installation and Problems

Installing a thermostat means replacing the wall control that tells your air conditioner or heat pump when to run. One maker's ins…

Thermostat Settings: Summer, Winter, Fan

There is no one correct thermostat setting, but public sources agree on where to start. For cooling, UF/IFAS Extension says 78°F o…

How to Reset an AC Unit

To reset most residential air conditioners, set the thermostat to OFF, wait a few minutes, then turn off the breakers serving the …

How to Turn On Your Air Conditioner

To turn on a central air conditioner, set the thermostat mode to COOL, set the fan to AUTO, and set the target temperature a few d…

Why Your AC Is Not Blowing Cold Air

An air conditioner that runs but does not blow cold air is usually caused by a simple issue you can check yourself: a thermostat f…

Why Your Outdoor AC Unit Is Loud

The kind of noise usually points to the cause. Rattling and buzzing often mean loose hardware or debris, humming with no start usu…

AC Filter Replacement: Which Filter to Buy and How Often to Change It

Match the size printed on your old filter, check it every month, and change it when it looks dirty. ENERGY STAR says to change it …

What BTU Means for an Air Conditioner

BTU measures how much heat an air conditioner can remove from a space each hour, so a higher BTU rating means more cooling capacit…

Which Way Does a Furnace Filter Go?

Every furnace filter has an arrow printed on its cardboard frame, and that arrow shows the direction the air flows through it. The…

AC Capacitor and Fan Failures: What the Parts Do and Who Should Replace Them

Changing an AC capacitor is work for a licensed HVAC technician, not a homeowner project. A capacitor is a small electrical part t…

AC Compressor Problems: Turning On and Off, and a Bad Compressor

The compressor is the pump of an air conditioner: it circulates refrigerant, the working fluid that moves heat out of your home. M…

AC Condenser: What the Outdoor Unit Does and How It Fails

An AC condenser is the outdoor unit of a central air conditioner or heat pump, and its job is to release the heat the system colle…

AC Freezing Up: What the Ice Means and What to Check First

An air conditioner freezes up when the indoor coil gets too cold and the moisture on it turns to ice. Bryant, Trane and a Departme…

AC Installation Done Right: Evacuation, Charging and Commissioning

A correct central air conditioning installation is proven by readings, not by cold air on day one. After the equipment is set, the…

AC Maintenance Checklist for Florida Homes

Genuine Florida AC maintenance covers cleaning the indoor and outdoor coils, clearing and treating the condensate drain line, chan…

AC Noises Decoded: Buzzing, Humming, Hissing, and Rattling

Each family of air conditioner noise points at a different mechanism: buzzing is usually electrical, humming is usually a motor tr…

AC Not Turning On: What to Check Before You Call

An air conditioner that will not turn on at all is almost always a power or control problem, not a refrigerant problem: dead therm…

AC Refrigerant Leak Repair: Find-and-Fix vs Top-Off

An air conditioner's refrigerant circuit is a sealed loop, so refrigerant is never used up in normal operation — if the charge is …

AC Repair or Replace: A Framework for Deciding

Decide by weighing a few factors together rather than any single one. Consider the system's age against how long units of its type…

AC Smells Like Burning: What It Means and What To Do

A burning smell from an air conditioner has exactly one common benign explanation: a brief dust burn-off when electric heat strips…

AC Surge Protection in Florida

In the Tampa Bay area — statistically among the most lightning-active regions in the United States — surge protection for an air c…

AC Tonnage and Sizing: What 3, 4 and 5 Tons Mean in Florida

An A/C ton is a measure of cooling capacity, not weight and not house size. One ton is 12,000 Btu per hour, and a Btu (British the…

AC Troubleshooting: From Symptom to Likely Cause

Effective air conditioner troubleshooting starts with five safe checks that resolve a meaningful share of no-cool calls without a …

AC Won't Turn Off: Why a System Runs Past Its Setpoint

An air conditioner that will not turn off is one of three different problems wearing the same disguise. If only the indoor fan run…

Air Conditioner Leaking Water: Where It Comes From and What To Do

Every air conditioner makes water: the cold indoor coil condenses moisture out of the air, and in a humid climate that adds up to …

Air Duct Cleaning: When It Is Worth Doing

Air duct cleaning is the mechanical removal of dust and debris from inside a duct system, and it is a condition-based service rath…

Air Handler Location in Florida: Attic, Garage or Closet

An air handler is the indoor unit of a central air conditioner. It holds the blower and the evaporator coil, the cold coil that pu…

Central Air Conditioning System Types

A central air conditioner cools a whole house through ducts, the channels that carry air to each room. Most are split systems: an …

Central Air for a House Without Ducts: Your Real Options

A house with no ductwork has four ways to get whole-house cooling: a new duct system, a small-duct high-velocity system, a ducted …

Central Heating in Florida Homes

Central heating means one heat source that warms a whole house, and in Florida that source is most often a furnace or a central he…

Chiller System: How It Works and Whether It Fits a Building

A chiller system makes chilled water in a central plant and pipes it through the building. The water goes to air handlers, indoor …

Cooling a Home Addition, Garage Conversion or Sunroom

A room addition, converted garage or sunroom usually leaves three cooling choices: extend the existing ducts, add a ductless mini-…

Duct Booster Fan: How It Works and Whether It Fits Your Home

A duct booster fan is a small fan that sits in a duct, or in place of a vent cover, to push more of the system's air toward one ro…

Duct Sealing vs Duct Repair: What's the Difference?

Duct sealing closes the small gaps, cracks, and loose joints that let conditioned air leak out of otherwise intact ducts, usually …

Ductless Mini-Split Repair: What the Code Means and What a Technician Checks

A mini-split is a ductless air conditioner or heat pump: an outdoor unit joined to one or more indoor units by refrigerant lines a…

Ductless Mini-Splits: How They Work and When They Fit in Florida

A mini-split is an air conditioner that needs no ducts. An outdoor unit holds the compressor, and thin refrigerant lines carry hea…

Ductwork in Florida: Leaks, Airflow and Installation

Ductwork, also called HVAC ductwork or air conditioning ductwork, is the network of tubes that moves air from your heating or cool…

Ductwork Insulation: What Fits Your Home

Duct insulation is a layer around, inside or built into a duct that slows the heat moving through the duct wall. R-value measures …

EPA 608 Certification and the Refrigerant Rules Homeowners Should Know

EPA 608 certification is the federal credential for technicians who work on the refrigerant side of an air conditioner or heat pum…

Evaporative Coolers in Florida: How They Work and Why Humidity Matters

An evaporative cooler, also called a swamp cooler or an air cooler, cools air by passing it over wet material so that water evapor…

Fan Coil Units: How They Work and Who Maintains Them

A guide prepared for the Department of Energy by Pacific Northwest National Laboratory defines a fan coil unit as a small terminal…

Florida HVAC Contractor Licenses: Class A, Class B, Mechanical, and How to Check One

Florida licenses air-conditioning work under chapter 489 of the Florida Statutes. The statute names Class A and Class B air-condit…

Furnace Replacement Cost in Florida: What Drives It

Furnace replacement cost depends on more than the furnace: a Department of Energy (DOE) guideline says installed cost can vary wid…

Furnace Types and Efficiency: What AFUE Means

A furnace is a heating appliance that warms air in one place and sends it through ducts to the rooms of a house. This page sorts f…

Furnace Won't Ignite: The Ignition Sequence and Where It Fails

A gas furnace lights through a strict sequence of proofs: the thermostat calls, the inducer motor establishes draft, a pressure sw…

Good Humidity for a House: The Range, the Reading and What to Check

The EPA says that, if possible, indoor humidity should stay below 60 percent, ideally between 30 and 50 percent. That is relative …

Heater Not Working in Florida: Why Heat Fails on the First Cold Morning

In Florida, most homes heat with a heat pump backed by electric strip heat, and that system sits unused for the better part of a y…

Heating Tune-Up: What It Covers and What to Leave to a Pro

A heating tune-up is a contractor's yearly check of the whole heating system, best done in the fall. For gas or oil heat, ENERGY S…

High-Efficiency AC in Florida: What the Ratings Show and Miss

Federal rules set a minimum for new split-system air conditioners in Florida. A split system has separate outdoor and indoor units…

Home Ventilation in Florida: Fresh Air, Fans and Humidity

Ventilation is the intentional exchange of air between the inside of a home and the outdoors, and EPA says it helps remove or dilu…

How AC Warranties Work and Transfer in Florida

A manufacturer's air conditioner warranty covers defects in the equipment's parts for a set period, but the exact length and terms…

How an Air Conditioner Works

An air conditioner does not make cold air. It moves heat out of your house using a refrigerant that absorbs heat indoors, carries …

How Long Do AC Units Last in Florida?

Nationally a central air conditioner is commonly cited as lasting about 15 to 20 years, but in Florida the realistic range is shor…

How Often Should You Clean Air Ducts? What a Proper Visit Includes

EPA's guide to duct cleaning sets no schedule: it recommends cleaning ducts only as needed. It names three reasons to clean: subst…

How to Choose the Right AC Size for a Florida Home

The right way to size an air conditioner for a Florida home is a proper load calculation that accounts for the home's square foota…

How to Compare HVAC Replacement Quotes

Two HVAC replacement quotes are comparable when they describe the same job in the same terms. That means a load calculation for yo…

Hurricane Season HVAC Prep in Florida

Before a storm: cool the house down early, then shut the system off at the thermostat and the breaker before conditions arrive — a…

HVAC Blower Motor Repair: What to Check and When to Call

The blower is the indoor fan that moves air through your ducts, the passages that carry it to each room. The blower motor is the p…

HVAC Inspection Before Buying a Home

A pre-purchase HVAC inspection is a focused evaluation of a home's heating and cooling system before you buy, covering the equipme…

HVAC Permits in Florida: What They Are and Why They Matter

In Florida, replacing or installing HVAC equipment generally requires a permit from the local building department, and a licensed …

HVAC Zoning: How Zone Dampers Work and When Zoning Fits

An HVAC zoning system splits one duct system into areas, each with its own thermostat, and uses motorized dampers (movable flaps i…

Industrial Air Conditioners: Types and How to Tell Them Apart

Federal law files commercial packaged air conditioners under “industrial equipment”. Federal rules sort that equipment by how it i…

Mini-Split Installation: What Drives the Job

Mini split AC installation comes down to five physical decisions, and each one changes the size of the job. They are the number of…

Mobile Home Air Conditioning: HUD Code, Ducts and Wind

Air conditioning in a manufactured home, often called a mobile home, is built around a federal rulebook: the HUD Manufactured Home…

Mold in HVAC Systems: Why Florida Humidity Makes It Common

Mold grows in air conditioners because the system combines the three things mold needs: moisture, organic dust, and darkness. In a…

Package Unit vs Split System: What Differs

A packaged unit, also called a package unit, is a central air conditioner or heat pump built as one outdoor cabinet. A split syste…

Portable Air Conditioners: Single Hose vs Dual Hose, and How Capacity Is Rated

A portable air conditioner cools one room and sends its heat outside through a hose. A single-hose unit takes that air from the ro…

R-22 to R-410A Conversion: What It Really Means

A true R-22 to R-410A conversion is usually impractical, and in most cases "converting" an R-22 system really means replacing it. …

R-410A Phase Out After 2025: What Homeowners Can Still Do

If you own an air conditioner or heat pump that runs on R-410A, the R-410A phase out can sound like a deadline for your equipment.…

R-454B vs R-32: The New AC Refrigerants

R-454B vs R-32 is the question a homeowner runs into when two AC or heat pump quotes list different refrigerants. One quote says R…

Return Air Vent Too Small: Symptoms and Why It Matters

A return air vent is too small when it cannot feed the blower enough air to match what the system pushes out, which starves the eq…

The AC Line Set: Reuse or Replace

An AC line set is the pair of copper tubes that carry refrigerant between the outdoor unit and the indoor coil. Refrigerant is the…

The Evaporator Coil: Function, Cleaning and Problems

The evaporator coil is the indoor coil of an air conditioner, where refrigerant absorbs heat from your house air and moisture in t…

Through-the-Wall AC Units and PTACs: What the Wall Sleeve Decides

A through-the-wall AC and a PTAC both sit in a hole cut through an outside wall, but federal rules treat them as different product…

Variable-Speed Air Handler: What It Is and Why It Matters

A variable-speed air handler uses a blower motor that can run at many different speeds instead of just on or off. By adjusting air…

What does a humidifier do, and do I need one in Florida?

Usually no. In Tampa Bay the outdoor air is moist for much of the year, and the EPA's indoor ceiling is 50 percent relative humidi…

What Is HVAC? The Parts of a Florida Home's System

HVAC stands for heating, ventilation and air conditioning. In a home it is the set of equipment that cools or heats the air, moves…

What Size Mini Split Do I Need? Sizing Room by Room

A mini-split is sized one room or zone at a time, and each indoor unit gets its own capacity in Btu per hour. A ton of air conditi…

When to Get a Second Opinion on an AC Repair Diagnosis

Get a second opinion whenever a diagnosis carries big consequences, especially a recommendation to replace the compressor or the w…

Where to put carbon monoxide detectors in a Florida home

Put a carbon monoxide alarm on every level of the house and one outside each separate sleeping area, close enough that it will wak…

Whole-Home Dehumidifiers in Florida: When You Need One, and What to Ask

A whole-home dehumidifier works through your home's ducts. It treats the whole house instead of one room. Whether you need one com…

Why the Upstairs Is Always Hotter: Two-Story Uneven Cooling

In most two-story homes the upstairs runs hotter because heat rises, the upper floor takes more sun and roof load, and a single-zo…

Why Your AC Can't Keep Up With the Heat

Our reading: an air conditioner that can't keep up with the heat on a hot afternoon fits one of three situations. It may be hotter…

Why Your House Feels Humid With the AC Running

Air conditioners do remove humidity, but only as a byproduct of cooling, and only while the indoor coil stays cold and wet long en…

Window AC Size Chart: What BTU Fits Your Room

ENERGY STAR's room air conditioner chart ties window air conditioner size to the floor area of the room. It lists 5,000 BTU per ho…

Window Air Conditioners: Types and When to Use One

A window air conditioner is a self-contained cooling unit that sits in a window opening and cools one room, and federal rules trea…