Arizona hvac services

HVAC Terminology


A-Z Glossary of Common HVAC Terms


Air Conditioner

The air conditioner is a device that cools and dehumidifies the air, making your space comfortable. It’s like a superhero that removes heat and humidity, circulating cool air through ducts and vents. In short, it’s a vital part of the whole HVAC setup.

Air Handler

The air handler, or the air handling unit (AHU), is the device that moves conditioned air all around your place. It’s got essential bits like the blower and filter that keep the air flowing just right. You’ll usually find it indoors, perhaps in an attic or utility closet, working together with the outdoor unit to keep your indoor temperatures comfy.



The compressor, right at the heart of your HVAC system, is a big deal. It’s the MVP in the refrigeration system, cranking up the pressure and temperature of that refrigerant liquid. Why? Because it helps with the whole heat-absorbing and heat-releasing magic that keeps your place cozy. It’s like a traffic cop for the refrigerant, shuttling it back and forth between the indoor and outdoor units for peak performance.

Condenser Coil

Let’s step outside for a moment and talk about the condenser coil. This part, also known as the outdoor coil, teams up with the compressor to kick unwanted heat out of your space. By turning refrigerant gas back into a liquid, it says, “Hey, heat, you’re outta here!” This coil typically hangs out in your outdoor air conditioning or heat pump unit.



Dampers make sure that air goes where it’s supposed to go. They’re important for keeping indoor temperatures comfy by balancing the airflow in different areas. And speaking of keeping things comfortable, there’s the dehumidifier, a device that cools the air so that water vapor turns into a liquid. This liquid can then be drained or removed to keep your space just right. Understanding dampers and dehumidifiers is key to making your HVAC system work its best.

Ducts and Ductwork

These are like the highways that make sure air gets where it needs to be. Properly designed and installed ducts, along with a well-behaved ventilation system, are a must for good indoor air quality and energy efficiency. They ensure the air flows evenly and everyone’s comfortable. Regular check-ups for your ducts and the ventilation system, along with keeping an eye on fresh air intake, are the keys to keeping things running smoothly.


Energy Star Rating

The Energy Star rating is a label. When you see this label, you know you’re looking at a product that’s met some pretty strict guidelines from the Environmental Protection Agency (EPA). It’s all about making sure your HVAC equipment is energy-efficient. Picking equipment with the Energy Star stamp means you’re in for some energy savings and lower utility bills. So, keep an eye out for it when you’re shopping for new HVAC gear.

Evaporator Coil

Now, the evaporator coil, tucked away in the indoor unit of your air conditioner or heat pump, is a real cool customer. It’s grabs heat from the indoor air and helps the compressor do its job. Keep this indoor coil in good shape, and you’ll be chillin’ when it comes to cooling.



The flue is what helps get rid of the byproducts of burning fuel in your heating system. It’s like the chimney for your furnace, making sure everything goes up and out safely and efficiently. Regular maintenance is essential to prevent blockages and ensure that things are venting properly.

Forced-Air System

The forced-air system uses a fan to spread that nice, warm or cool air all around your place. But remember, it’s essential to keep the air filter clean and do some duct cleaning now and then to keep the air quality and system efficiency top-notch.


Freon, the old-school refrigerant. But here’s the thing, it’s not great for the ozone layer, so it’s getting phased out. The trend now is eco-friendly refrigerants like R410A. And let’s not forget, certified technicians are the heroes who should handle and dispose of Freon properly.

Fuel Efficiency

Fuel efficiency is all about how effectively your heating system turns fuel into heat. The more efficient, the better, and the less energy and money you’ll burn through. High-efficiency HVAC systems are what make this happen, and Energy Star appliances are the ones to watch for.


Heat Exchanger

The heat exchanger in your furnace takes the heat from the combustion process and shares it with the surrounding air. But keep it in top shape because cracks or leaks could spell trouble, including the risk of carbon monoxide. Annual check-ups by a licensed technician are your ticket to warmth and safety.

Heat Loss

Heat loss is the transfer of heat energy from a warmer object to a cooler object. In the context of HVAC terminology, heat loss can occur through the walls, roof, windows, and doors. It can also occur through air leaks around windows and doors, and through the heating and cooling system.

Heat loss can be reduced by insulating the building, sealing air leaks, and using energy-efficient appliances and lighting. A home energy audit can help identify areas where heat loss is occurring and recommend ways to reduce it.

Heat Pump

The heat pump is a versatile HVAC system that’s both a heating and cooling pro. With the right maintenance, it’s an efficiency champ. It can even team up with other HVAC systems for maximum effectiveness. Look for the Energy Star stamp of approval if you want to go the extra mile in saving energy.



Insulation is like a warm, cozy blanket for your building, keeping the temperature in check and preventing heat from slipping away through walls, attics, and floors. Upgrading your insulation can put a check on those heating and cooling costs. Different insulations have different R-values, which is a measure of their effectiveness in stopping heat from escaping.


Jumper Wire

A jumper wire is a quick fixer in the electrical world. It’s a temporary bridge that connects or bypasses electrical components, helping technicians troubleshoot and test things out. Safety first, though – only trained technicians should handle these wires.


Kilowatt (KW)

Kilowatts (KW) are the energy currency in the HVAC world. They measure the electrical consumption of your HVAC system. Knowing your system’s KW rating can help you estimate your energy usage and costs.


Load Calculation

A load calculation is what helps HVAC technicians custom-make your system to fit your needs perfectly. It considers things like the size of your place, insulation, and the climate, so your system is just the right size. An undersized system can’t keep up, while an oversized one can lead to a lot of wasted energy. So, proper load calculation is a must for comfort and efficiency.


Manual J

Manual J is a load calculation standard used in calculating the heating and cooling load of a residential building. It considers your home’s size, insulation, and climate to figure out the perfect system for you. HVAC experts swear by it to make sure you’re comfy and your system is efficient.


Outdoor Unit

The outdoor unit is the big guy outside, housing the condenser, compressor, and cooling unit. It’s where all the heat-transfer action happens to keep you cool. Just make sure it’s in a well-ventilated spot for peak performance, and remember that regular maintenance is the key to keeping it running smoothly.


R-410A (Puron)

This is an eco-friendly refrigerant that’s becoming increasingly popular. It’s replacing the old R-22 because it’s kinder to the ozone layer. HVAC systems that use Puron need special equipment and expertise for servicing, so make sure you’ve got the pros on your side.


Quad Zone

A quad-zone HVAC system provides control over four different areas. Each zone has its own thermostat, and it’s perfect for larger spaces. It helps you save energy by only heating or cooling the areas that need it. Just remember, setting up a quad-zone system takes planning and some ductwork magic.



Refrigerant is the magician in your HVAC system, absorbing and releasing heat to keep you comfortable. The right amount is vital for peak performance, and leaks can put a dent in your efficiency. So, leave refrigerant handling to the experts who know how to do it safely and follow the environmental rules.



The thermostat is what you use to set the temperature of your HVAC system. Modern thermostats offer fancy features like programmable settings and smart controls, letting you save energy and money. Just be sure to put your thermostat in the right spot for accurate readings.


Unitary System

The unitary system is the all-in-one package. It’s got all the heating and cooling components in one neat unit, perfect for smaller spaces. Keep it in top shape with regular maintenance to enjoy peak performance and efficiency.


Variable Air Volume

Variable Air Volume (VAV) is the adjustment of the airflow as needed, making it super-efficient by delivering just the right amount of conditioned air. It’s perfect for big buildings and homes with different zones, giving everyone their personalized comfort.



Your HVAC warranty is a security blanket for repairs or replacements. Different parts might have different warranty terms, and you usually need to register it to make it official. Keeping up with regular maintenance and professional installation can help you keep your warranty valid, saving you money on future repairs.


Yearly Energy Costs

Yearly energy costs are the total amount of money you spend on heating and cooling your home in a year. They are calculated by multiplying the number of kilowatt-hours (kWh) your HVAC system uses by the cost of electricity per kWh.

The higher the SEER and AFUE ratings of your HVAC system, the lower your yearly energy costs will be. Proper installation and maintenance are also important for energy efficiency. To save energy and money, use a programmable thermostat, plug air leaks, and swap out air filters regularly. An HVAC professional can help you make the most of your system.



Zoning is the ability to give every room its own thermostat and personalized comfort settings. It’s all about dividing your building into different temperature zones and only heating or cooling the areas that need it. Pro HVAC designers and installers are your go-to for setting up an effective zoning system.

HVAC Acronyms

ACH (Air Changes per Hour)

ACH is basically about how many times the air inside a place gets replaced with fresh outside air in one hour. Why does this matter? Well, it’s important when keeping the air clean and maintaining good indoor air quality. In Arizona, the specific ACH requirements can vary depending on the type of building and what it’s used for.

AHRI (Air Conditioning, Heating, and Refrigeration Institute)

AHRI is short for the Air Conditioning, Heating, and Refrigeration Institute. It’s this non-profit group that looks out for us by representing the manufacturers of HVACR equipment in the United States. They set the standards for how well these systems should work, and they even certify the products that meet those standards.

AFUE (Annual Fuel Utilization Efficiency)

AFUE, or Annual Fuel Utilization Efficiency, is all about how efficiently a gas furnace turns natural gas or propane into heat. It’s measured as a percentage. The higher the percentage, the more efficient the system. In Arizona, they want new gas furnaces to have a minimum AFUE rating of 80%, but you can go even higher for better efficiency and energy savings over time.

BTU (British Thermal Units)

BTU is short for British Thermal Units. This is how we measure the heating or cooling capacity of HVAC systems. In Arizona, we often measure the size of an HVAC system in BTUs per hour, which tells you how much energy is needed for heating or cooling. It’s like the power rating of your system.

But here’s the twist: the right BTU rating depends on things like the size of your space, ceiling height, insulation, and how much sunlight it gets. To figure it out, it’s a good idea to talk to a licensed HVAC contractor who can give you the scoop on the right system for you.

HERS (Home Energy Rating System)

HERS, or the Home Energy Rating System, is a scorecard for how energy-efficient your home is. It uses something called the HERS Index, which goes from 0 to 150. The lower the number, the better – that means your home is more energy-efficient. Certified HERS Raters are the judges. They come over, evaluate your place, and give you a report that tells you what areas could use a little energy-saving TLC. These reports are handy, especially if you need building permits or want an energy-efficient home certification in Arizona.

IAQ (Indoor Air Quality)

When we talk about IAQ, we’re all about keeping the air inside your place healthy and comfy. Bad IAQ can lead to all sorts of problems like breathing issues and allergies. To keep things in tip-top shape, you need proper ventilation, air filtration, and humidity control. That’s where regular HVAC maintenance comes in – it helps improve indoor air quality. You also want to keep an eye on things like carbon dioxide levels and make sure you’re not letting pollutants build up inside. After all, it’s all about having a comfy, healthy home environment.

MERV (Minimum Efficiency Reporting Value)

MERV, or Minimum Efficiency Reporting Value, tells you how good your filter is at catching those tiny particles floating in the air. The higher the MERV rating, the better it is at catching small stuff. You’ve got to pick the right MERV rating that suits your needs and your HVAC system. And don’t forget, changing those air filters regularly with the right MERV rating helps keep the air clean and protects your HVAC gear.

NATE (North American Technician Excellence)

When it’s time to get your HVAC system fixed, you want someone who knows what they’re doing. That’s where NATE certification comes in. Technicians with NATE certification are the pros of the HVAC world. They’ve got the skills and the smarts to diagnose and repair your system accurately. The best part? They’re always learning and keeping up with the latest in the industry. So, when you pick a NATE-certified technician, you’re making sure your HVAC lasts longer and works better.

R-22 (Refrigerant 22)

Refrigerant 22, or R-22, is what they used to put in older HVAC systems. But since it’s not great for our ozone layer, they’re phasing it out. The new trend is going eco-friendly with refrigerants. Upgrading to an HVAC system that uses these greener refrigerants can save energy and reduce our impact on the environment. The best move is to chat with HVAC experts to figure out how to transition away from R-22.

SEER (Seasonal Energy Efficiency Ratio)

SEER, or Seasonal Energy Efficiency Ratio, is all about how efficient your HVAC system is at cooling. It’s like the efficiency rating for your air conditioner. The higher the SEER rating, the more efficient the system. That translates to lower operating costs and energy savings. So, when you’re shopping for a new HVAC system, understanding SEER ratings is a smart move. You can even boost the efficiency with something called an economizer, which helps cut down on energy consumption.