There was a time when “HVAC” really was a term thrown about only by industry professionals and those wealthy enough to pay for it. Now, however, the entire industry has opened up. Google is littered with “what is HVAC” searches.

It’s become an almost generic term for air conditioning, used synonymously by people in all environments. But what does HVAC mean, exactly? How does it factor into your home or business, will it be heating or cooling? And what, if anything, is the difference between it and air conditioning?

These are the important questions, as we move into a world of better and better air control systems for spaces of all shapes and sizes. Because, ultimately, even with dozens of options to choose from, the only way to make a truly informed decision is to be, well, truly informed.

So join us, as we define HVAC, define air conditioning, and break down the differences between these two concepts.

WHAT IS HVAC?

Let’s start right off with an important question: “What does HVAC stand for?”. Short for heating, ventilation, and air conditioning, HVAC is responsible for heating and cooling a building. It’s also a source of proper ventilation, allowing for moisture to escape.

HVAC units can take on many shapes and sizes, all offering different benefits depending on their design and the spaces they’re being used in. Units may include any combination of the following:

• Boilers
• Air conditioning units
• Ducts and moisture vents

Not all HVAC units are air conditioning units, even though AC units are included under the HVAC umbrella. As outlined above, what’s important to understand is that it’s actually a larger term. Think of it as an umbrella term that applies to all sorts of interrelated air control systems.

A CLOSER LOOK: HOW DOES YOUR HVAC WORK?

There are instances where the HVAC components may operate independently of each other. What’s more common, however, is for each component to work alongside the others. These so-called “combined systems” include both central heating and AC systems.

But make no mistake: your HVAC system is more than just a convenient way to warm up or cooling the space you live or work in. It’s a way to fully transform your indoor air quality and create a comfortable environment for everyone inside.

HVAC systems are available in several different variations. However, even with that said, at their core, they’re all based on the same essential build concepts. And it starts outside, not inside.

Fresh air is sourced and brought in from the outside environment by way of a process called “ventilation”. This can be carried out in one of two ways.

NATURAL VENTILATION

Ventilating your space naturally is done without specialized equipment, construction, or add-ons. We see this present in most homes, actually, in the form of any entry and exit points into the building. When the natural air outside moves through your windows, doors, and vents of its own accord, that’s natural ventilation.

Where is this most useful? Natural air exchanges like this are important in replenishing your oxygen levels, for starters. It’s also useful in removing odours and excess moisture from your home, as well as filtering out carbon dioxide.

MECHANICAL VENTILATION

Next, we have mechanical ventilation. This is a system that uses mechanical systems to transport air both into and out of the building. Old-fashioned architecture made it so most buildings had ready access to natural ventilation. Most homes, businesses, and official buildings made use of doors and windows to bring natural air from the outdoors, indoors.

Modern architecture is different, however. Contemporary builders opt for creating much more tightly-sealed homes, in general. This is a design philosophy that makes mechanical ventilation all the more important in households with HVAC systems.

Air enters the building using a specially designed air inlet unit, where it is immediately put to work. Air enters via the filter and is routed to different areas where it will be most needed. Specifically, it will be used in removing dust and dirt, allergens, and various other particles. This same air is used both in heating and cooling processes, and also works against excess humidity in the air.

Finally, once the air has been filtered and brought up or down to the appropriate temperature, it is headed home. In the case of a central system, this movement takes place via a network of ducts, allowing the air to travel wherever it is needed.

WHAT IS AIR CONDITIONING?

An air conditioner or AC system is specifically designed to cool or heat the air. In some circles, a contractor may call any unit that controls the air, whether hot or cold, an air conditioner.

For our purposes, however, and to keep the process as uncomplicated as possible, we won’t be using this convention. We’ll break it down like this: a system designed to condition the air is an air conditioner. Any system that works to cool or heat up the air while pushing out moisture via air vents would be referred to, specifically, as an HVAC unit.

We need to be careful here, most if not all AC units heat as well as cool these days, they refer to this as a “heat pump” which in essence is reversing the refrigeration cycle to provide heat, more and more these days buildings are dispensing with traditional “wet” systems as air conditioning systems have become more reliable and more importantly very efficient against fossil fuels.

A CLOSER LOOK

There are different kinds of air conditioning and HVAC systems. Let’s take a closer look at some of the options available;

Window Unit

A window air conditioner or heater is a small unit that is installed in and sits on the inside of a window sill. These AC units are usually smaller but actually offer a pretty powerful output. In spite of this, however, they are best used in small spaces for maximum efficacy. Studio apartments and small rooms work best, in this regard.

One big benefit of window units is their price. For the budget-conscious, this is one of the cheapest cooling options out there, especially for the quality of the product. Expect to pay only a few hundred pounds at a time, both for the unit itself and for installation.

Central Air (Air Handling Unit, AHU)

Central air conditioners are commonplace for cooling and heating. They’re especially useful in large spaces, where the interconnecting air ducts guide and release air to the rooms where it is needed.

The system itself will include both outdoor and indoor parts. Because of the size of the installation, these tend to be lifelong investments, put into buildings that owners own for many years.

They also involve big investment, initially. The system itself, however, is one of the most effective and has been known to last up to 20 years or more under the right circumstances.

The Mini Split System

The mini-split system is quite similar in design to central air. The big difference is the fact that the ductwork is largely removed and in its place refrigeration pipework is installed.

One of the biggest draws when it comes to ductless systems such as these is in the reduced cost of operation.

The system is more aesthetically pleasing than some other options, since there is no need to install complicated ducts.

And Now You Know…

When we try to define HVAC, air conditioning, and the differences between them, we immediately run into a problem. The idea of “what is HVAC” and “which one is air conditioning” has a simple answer: there is no real difference. Air conditioning is a subsection of HVAC, with units focusing more on moving air through a space.

It’s no secret that a properly functioning HVAC system is crucial to the comfort of your home. But when it comes time to hire an HVAC contractor, how can you be sure you’re getting someone who will do the job right? Here are some important questions to ask before hiring an HVAC contractor in Annapolis, MD:

ARE YOU LICENSED AND INSURED?

When hiring an HVAC contractor, you want to be sure the company is properly licensed and insured. This protects you in case something goes wrong during the job. Be sure to ask for proof of both before moving forward.

When you ask about licenses and insurance, inquire about other credentials the contractor may have. This can include things like industry certifications or training. The more credentials a contractor has, the better.

WHAT’S YOUR EXPERIENCE?

You’ll want to hire a contractor with plenty of experience. Ask about the contractor’s history, how long the company has been in business and the types of projects the company typically works on. The more experience contractors have, the better equipped they will be to handle your project.

With these, you can also ask about references. Good contractors should be able to provide you with a list of past clients who can vouch for their work. This way, you can get first-hand accounts of what it’s like to work with them.

WHAT’S YOUR POLICY ON OVERTIME CHARGES?

Some contractors will charge you extra for overtime, and others won’t. It’s important to know the policy before hiring a contractor because this can be a significant cost if you’re not careful.

You need to understand how contractors charge for overtime. If they charge by the hour, you need to know their hourly rate. If they charge a flat fee, you’ll want to know how much that fee is.

CAN YOU PROVIDE A WRITTEN ESTIMATE?

When hiring a contractor, you’ll want to get a written project cost estimate. This way, there are no surprises down the road. The estimate should contain a list to show exactly what you’re paying for.

Be sure to ask about any other documents the contractor will need, such as a contract or proposal. These can give you additional information about the project and help you make an informed decision.

WHAT’S YOUR WARRANTY POLICY?

Most contractors will offer some warranty on their work. This protects you in case something goes wrong once the job is complete. Be sure to ask about the warranty terms, such as how long it lasts and what it covers.

You should also inquire about any other guarantees the contractor offers. For example, some contractors may guarantee their work for a certain period. Others may offer a money-back guarantee if you’re unsatisfied with the results.

This will help you understand what type of protection you have if something goes wrong. It is also safe practice to save all paperwork related to the warranty in case you need to use it later.

WHAT ARE YOUR PAYMENT TERMS?

HVAC contractors will typically require some payment upfront. This is usually a deposit that goes toward the project’s total cost. Be sure to ask about the payment terms before hiring a contractor.

You’ll also want to know when the final payment is due. Some contractors will require full payment upon completion of the job, while others will give you a grace period to make the payment. It’s important to know this so you can budget accordingly.

WHAT’S YOUR CANCELLATION POLICY?

Sometimes, you may need to cancel your project after hiring a contractor. Knowing the contractor’s cancellation policy is important so you don’t lose your deposit.

Some contractors will allow you to cancel without penalty if you give them enough notice. Others will charge a cancellation fee, which could be a percentage of the total project cost. Be sure to ask about this before hiring a contractor.

Your ventilation system in your home is one of the key elements of your family’s health. The air in your home can be filled with contaminants like airborne spores and germs and can be prone to mold and mildew. Poorly ventilated homes are far more susceptible than those with air conditioning and ventilation systems.

For allergy and asthma sufferers, poor ventilation is a well-known trigger, and creates a very unhealthy environment, causing unnecessary illness. By reducing dampness in the air, by lowering condensation levels, and removing dust and pollen from the air, ventilation systems makes the air cleaner, and your family healthier.

Ventilation systems undoubtedly improve the quality of the air you breathe and can also save you a lot of money. One important thing to know about ventilation systems is that with regular use, comes the requirement to maintain it. Maintenance can include cleaning filters, and general servicing to clean and ensure the system is working to its full capacity. There are of course many other reasons you should service your ventilation system.

Here are 4 Reasons You Need Your Ventilation Systems Serviced:

Preventative maintenance

The thermostat that helps to monitor the temperatures of your home is a critical part of your heating, cooling and ventilation system, and without regular maintenance the thermostat can stop working at the capacity or stop working altogether. This can cause your home’s temperature to become out of balance, resulting in the loss of your preferred thermal comfort levels. Preventative maintenance will pick up any small thermostat issues early, allowing you to replace it before it is too late.

Dirty Filters

Regular maintenance includes the cleaning or replacement of dirty or faulty filters. Dirty filters mean air flow will be restricted and the air will not be cleaned as it should be. The only way to ensure the filters are doing the job they are designed for is through maintenance. Filters should be cleaned seasonally, and if you are in a dusty area, it might pay to purchase an extra set of filters to keep in clean storage to replace between seasonal servicing. Dirty filters also reduce the efficiency of the system, forcing the system to run harder and cost you more.

To Rectify Improper Installations or Imbalanced Dampers

Sometimes installation can be rushed or not correctly carried out for many reasons, however servicing your ventilation system allows the technician to find and repair any errors that were previously made upon installation or adjustments. Your ducting can often become unattached inside your roof or walls if it isn’t installed correctly, which can cost hundreds of dollars a year on air going inside your walls rather than where you need it to be.

Incorrectly balanced ducting can also lead to hot or cold spots in areas of the home and servicing the system can easily rectify this problem. Ducting balance can also be altered for the seasons. You house position has a big impact on how the heat is circulated through your home, and some parts are almost always hotter or colder than others naturally. Your service technician can alter the ducting and rebalance it to suit the seasons, to ensure your home is a consistent temperature throughout, all year round.

To Ensure It Runs at Optimum Capacity

For your system to run at its peak performance level, a service technician needs to be able to find and fix problems or faults. This enables your system to run at its best all year. Maintenance is a cost that you might be hesitant at paying for, however when you think about costs of maintenance versus costs of repairs, the money really is worth spending. Just like you service your car, you should service your ventilation system to prevent large costs when something breaks.