What Happens When Return Vents Are Blocked?
- The system will have to work harder to take in air, ultimately pulling it in through minute cracks in the home's...
- The system may not be able to cool or heat as efficiently, driving up your utility bills and diminishing your comfort.
- You can actually freeze the air conditioner coils by blocking return vents. Frozen coils not...
Can you block a return air vent?
You should never block a return air vent as this can cause problems in air circulation, humidity, and toxic mold. As part of the HVAC system, return air vents help properly circulate air around your home, and by blocking an air vent you can damage your HVAC system which can be very dangerous. Reasons to Keep a Return Air Vent Clear
What happens if you cover a return vent?
A return vent will pull the paper toward it instead of blowing it away like a supply vent. The most obvious effect of covering return vents is that the air can't get back to the HVAC system.
Why can't I open my return vents?
Your return vents are usually larger than your supply vents. They don't have louvers like registers do, which means you can't open and close them. If you're still not sure, hold a piece of paper up to the vent while the system is running.
What happens if you block off your HVAC system?
If your HVAC system is designed this way, blocking off a single return vent can wreak havoc on the system and lead to: Pressure imbalances that let allergens and pollutants get pulled into your air supply from unconditioned areas. A drop in HVAC equipment efficiency, which results in an increase in energy consumption and operating costs.
Is it OK to block a return vent?
It's important not to block your return air vent because your HVAC system needs constant return air to work properly. Blocked air return ducts will cause your system to lose energy efficiency and cause premature failure of your HVAC system. This does not mean you don't have many options for hiding your return air vent.
Is it OK to partially block a cold air return?
Most residential cooling and heating systems operate as closed-loop systems. In a closed-loop system, air returns play an essential role, and it is important not to block them. Blocking a cool air return means a risk of freezing the air conditioner coils, causing a restriction of air flow.
Why do people block cold air returns?
Reasons People Close Vents Closing the vents throws off the balance and pressure, causing damage and forcing the unit to work harder. It can make the system less energy efficient, so leaving all vents open and unblocked is best.
Are return air vents necessary?
Return air vents are an important part of your HVAC system. These vents allow the air that is in your home to return to the system for heating or cooling in order to maintain the proper temperature in the home.
What happens if you block a vent in your house?
Proper Airflow is Important This constant push of air to a blocked air vent can create an increase in pressure, and when combined with inadequate airflow, it can cause damage to your HVAC system's heat exchanger. This damage can also lead to the exhalation of carbon monoxide and result in leaking ductwork.
Should cold air returns be sealed?
Return air ducts must be sealed and unobstructed — Sealing return air ducts is just as important as sealing supply ducts. Sealing all duct section connections with mastic, a specialized rubbery sealant, or with metal tape prevents air leaks.
Is it OK to put furniture in front of a return vent?
Home Inspection Insider explains that an air return vent needs 6-12 inches of space in front of it, and recommends that you do not put large, bulky furniture like couches and bookshelves in front of an air return vent.
What happens if there is not enough return air?
If there is not enough return air available, your HVAC system will not heat or cool properly. They must be properly sized — Return air ducts must be large enough to carry a sufficient amount of expended air back to your furnace, air conditioner, or heat pump.
Should every room have a cold air return?
While it is a myth that air return grilles are required in each and every room in the house, it is definitely necessary to have more than one of these grilles installed at strategic places in the house. The most important place to have these would be the bedroom.
What is the purpose of a return vent?
Return vents: What is a return vent? These vents suck the air from each room and send it back to the air conditioning or heating system. Return vents tend to be bigger than supply vents, and you won't feel any air coming from them. When an HVAC system delivers air to a room, it increases that room's air pressure.
How many return air vents should a house have?
Your Home Might Not Have Enough Return Vents Having several return vents (ideally one in every room, but even two or three is better than just one) creates consistent air pressure. If you have one return vent, your home is fine. Keep the doors to each room open so air can properly circulate.
Why does my return vent smell?
Unfortunately, mold or mildew growth from moisture in the air may be the root cause of the smell. As mold grows inside return air ducts, the air flowing through the ducts carries a musty odor to your rooms. These smells may cause headaches or aggravate health issues such as asthma or allergies.
What does blocking an air return vent do?
Blocking air return vents causes your system to work harder, as there is less air flow to move the air back to the furnace.
Where is the return vent located?
Return vents are usually larger than heat registers and can generally be found close to the ground or in the floor in older homes or on a wall close to a ceiling in newer homes.
Do return vents work?
Air return vents attract a lot of dust and cleaning them regularly will ensure they continue to work efficiently. It may be a small thing, but making sure your air return vents are free from obstructions will make a huge difference in the overall performance of your HVAC system.
How to tell if a duct is blocked?
You can generally identify a blocked air duct by a distinct drop in heating and cooling efficiency, increased energy costs and occasionally a musty, dusty smell throughout the home. Blockage usually comes over time, by a buildup of dust and debris that just accumulates until it begins choking the system.
What does it mean when your return air ducts are leaking?
Leaky return air ducts. A leaky duct specifically refers to ductwork that has become loose or damaged. You can usually spot this from musty smells throughout the home, or weak heating and cooling. Loose and leaky ductwork isn’t necessarily a consistent issue, but we do find it to be a common one.
What is return duct?
Return ducts essentially passively ‘collect’ the air in your home, pulling it into the system to be filtered, dehumidified and conditioned to reach the desired temperatures.
How to get a good idea of what's wrong with your duct system?
To get a good idea of what’s wrong with your duct system, it takes time and effort to really get in there and see what has gone wrong! To avoid these problems as much as possible and reduce the frequency of the, be sure to change your filter frequently and clean the vent grate.
What happens if you block a vent?
Perhaps the most obvious (and most dangerous) result of a blocked vent is that it will cause a fire. How? When you’re forcing your system to overwork, as mentioned in our first point, you put your furnace at high risk of setting on fire.
Why does air pressure increase when you close a vent?
When you close air vents or block them with furniture, the same amount of air is being pushed through your ventilation system but with increased pressure because of limited opportunities for air flow.
Why is there mold in my house?
Mold and Mildew. Because of humidity, moisture will collect behind the blocked vent, causing mold and mildew to not only fester, but to infect the air blowing through your entire house. This is a terrible scenario for any homeowner, but it can be especially dire for allergy and asthma sufferers.
Does a frozen AC coil cause a leak?
Not only does it force your HVAC system to work harder—shortening its lifespan—but it also results in frozen air conditioning coils, overheated furnaces, cracked heat exchangers, and leaks in duct systems. Those issues come with both danger to your home AND big price tags for repairs.
Why shouldn't you block cold air returns?
Why You Shouldn't Block Your Cold Air Returns. The vents that pump out conditioned air throughout your home likely come to mind when you consider HVAC air distribution. The cold air returns are just as important, though, and making sure that they're free from obstructions is vital to keeping your entire HVAC system operating reliably ...
How to keep cold air return registers unobstructed?
Keeping your cold air return registers unobstructed is the first step in maintaining proper airflow through your HVAC system. Make sure that the return vents are never blocked by furniture, area rugs, long drapes, large toys or other household items. Additionally, vacuum or dust the vent covers periodically to remove any collected debris.
What is the function of a cold air return register?
However, the most important function of the cold air return registers is ensuring ample airflow through the HVAC system.
How to promote good airflow?
To promote good airflow you should also: Check the system's air filter monthly and replace it as needed. Avoid closing doors to infrequently-used rooms or shutting any supply registers. Get your HVAC system assessed to see it has enough cold air return registers.
Can you have one return vent on each floor?
It used to be common for forced-air HVAC systems to have supply vents in every room, but only one return vent on each floor. If your HVAC system is designed this way, blocking off a single return vent can wreak havoc on the system and lead to:
How does cold air return work?
The function of the return side is fairly simple: cold, stale air is drawn into the ductwork through the return registers, it’s pulled through the air filter, then it’s delivered to the HVAC equipment where it’s reconditioned.
How to ensure there is always enough airflow in HVAC?
You can help ensure that there’s always sufficient airflow through your HVAC system by keeping your cold air return registers unobstructed by household items like long drapes, area rugs, furniture and children’s toys. You can also: Vacuum or dust your supply and return registers frequently to keep them free of debris.
What is the effect of less conditioned air on the system?
Less conditioned air output, which creates temperature and humidity control problems and a decline in your comfort level.
What are the two main sides of HVAC?
Your HVAC system’s air distribution network consists of two distinct sides: supply and return. Both sides must be fully functional for reliable HVAC performance, which makes it critical to keep your cold air returns unobstructed so air can flow unrestricted through the system.
Why won't my furnace get hot air?
If a particular room has a heating vent, but no return vent, it won't get as much hot air from the furnace because the room is already full of air that isn't going anywhere.
How does a furnace work?
The furnace sucks air through the return vents, which lowers the air pressure in the rooms in which the vents are located . Air comes into these rooms through the heating vents to equalize pressure, creating a circulation that warms the rooms. If a particular room has a heating vent, but no return vent, it won't get as much hot air from ...
Can you close more than one return vent?
This will direct the hot air from the furnace into the rooms with open return vents, warming them more. Some return vents have adjustable louvers for this purpose. It's important not to close more than one or two at a time, though, or the furnace might not have enough air to circulate. Advertisement. references.
