Delivering the right volume of air to the right spots in the home is critical when it comes to keeping you comfortable and ensuring your system doesn’t die prematurely! Too feel what your HVAC system might be feeling if it has improper air flow, just clench your teeth, and plug your nose and try to breath… you’re right, it can be done… but for how long, and at what cost to you?

WHAT IS A DUCT SYSTEM?

Like stated before, a duct system is responsible for delivering the right volume of air to the right spots in the home. One branch of the system carries conditioned air to the rooms in your home, and another branch brings the air back to the furnace or air handler to be reconditioned.

Most often small grills, like those you see in your kitchen, bedrooms, and living room, with adjustable dampers are used to supply the conditioned air. While larger grills with no dampers are used to return the air. A duct system is not a-similar to your heart and your cardiovascular system. The blower is the heart, and the trunks are the arteries/ veins.

In many older homes, the thought of duct sizing wasn’t something discussed, thus leading to the furnace or heart of the system having too small of supplies or arteries/ veins. Making it all worse, those pesky rules of thumb, were used as opposed to actual design and system requirements. An HVAC system with design flaws was unintentionally designed to struggle.

Newer homes however are in luck! In recent years the government has required that HVAC systems be designed and installed in accordance to an international code: The International Mechanical Code, Manual D, Manual J and Modern Refrigeration and Technology. This ensures that a system is ready and able to handle all that your climate and home can throw at it!

For the existing home, when it comes time to replace your HVAC system, you want to ensure you’re choosing a reliable contractor who has done a heat load, and is in accordance with the International Code. It is not to your advantage to assume you can replace the existing system with one of the same capacity, or just assume that a bigger unit will keep you “cooler/warmer.” PROPER SIZING IS CRITICAL!

WHAT DOES A DUCT SYSTEM AFFECT?

So we’ve addressed WHAT a duct system is, no let’s talk about why it’s important!

RELIABILITY AND LIFE:

Air that flows properly through a duct system can help avoid equipment failure!

1. Good air flow means there is less stress on the blower (heart) of the system
2. Proper airflow allows components, such as temperature limits and igniters in the furnace, and the compressor in the air conditioner, to cycle less frequently, avoiding overwork of the part and extending its life.
3. Good air flow helps avoid temperature swings. Large temp swings can decrease the life of the system due to longer run times.

COMFORT:

No more hot and cold spots throughout the home. With proper air flow, each room in the home is getting the correct amount of air, to ensure the home is at its comfort peak! If there is improper air flow, it will result in uneven temperatures that can range from mild to drastic!

If an imbalance issue can’t be adequately addressed by duct modifications, it might make sense to consider upgrading to two-stage or modulating furnaces and air conditioners, whose unique designs can assist in moderating temperatures in areas where airflow is less than optimum. These highly efficient and effective systems are worth a look, even if you have a great ducting system!

BILLS:

When air from a proper system is moved, it circulates effectively, without wasting any electricity or gas. As the system fights to overcome restrictions, it runs longer, thus increasing your utility bill!

NOISE:

A smooth air stream is what we are after, and is imperative for quiet operation of your equipment. The less friction or resistance to airflow, the better. A properly designed duct system, and a correctly sized blower motor in the furnace are important! Excess turbulence in the system generates noise and could possibly give you that “jet engine” noise associated with some furnaces!

WHAT CAN I DO TO HELP?

Thus far we have focused on the state of the duct system. There are a few things you can do to optimize your existing conditions!

1. Change your filters regularly, and make sure a dirty filter isn’t adding to your woes!
2. Make sure all grills and registers are open and unobstructed!
3. Dust return air grilles and supply registers often, keeping away that unwanted dust!

Inspect the sheetmetal on your system and look for any air gaps. If you see a joint that is not sealed, or has a visible gap, seal it up. This can be accomplished using foil tape and or mastic that can be purchased at most hardware stores. If you have any questions, don’t feel confident about your repair, or this kind of thing just isn’t your cup of tea, give your local HVAC contractor a call to assist!

For any and all questions, service or advice in the Oklahoma City, Oklahoma area contact Yarbrough and Sons Heat and Air!

Published: January 30, 2019