What Happens if You Block Cold Air Return?

As a homeowner, you’re probably aware that the vents in your home help with air circulation. You will find these vents in the ceiling, hallway, and the walls in some rooms. However, some of you don’t like how they look and may decide to block the openings, but you’d be making a mistake.

When you block cold air return from a vent it makes the HVAC system work overtime to ensure airflow continues to be efficient through the house. The blockage causes inconsistency in airflow, and the HVAC system may malfunction because of the frequent wear and tear it suffers from overworking.

It’s a terrible idea to block the vents in your house, as these blocks hinder the flow of fresh air inside. In this article, we’ll go through the changes in airflow and the impact of blocking cold air vents.

Why You Shouldn’t Block Cold Air Return?

You shouldn’t block cold air return because stopping it makes your HVAC system go into overdrive to work efficiently. The air circulation becomes inconsistent and it might even be unsafe to breathe for the people at home. Additionally, your electricity bills will be higher as the system draws more power to work efficiently.

1. It Makes Living Spaces Dangerous

When the vents within a house are blocked, the atmosphere inside isn’t healthy. Aside from stale air, blocking the cold air return vents can lead to a possible crack in the heat exchanger as it gets overloaded.

A gap in the heat exchanger means a carbon monoxide leakage, which can be life-threatening in the long run. If you don’t get a professional to fix it immediately, you are putting your house and the people inside it in danger of carbon-monoxide poisoning. 

Read: Symptoms Of Not Enough Return Air

2. The Monthly Bills Will Soar

A common misconception about cold air return vents is that blocking them may help you save money on electricity. Because, logically, fewer vents = more savings. However, this isn’t the case, and you may actually end up spending a lot more. 

An inefficient HVAC system leads to improper heating and cooling. You will not get the right balance of temperature and might end up straining your HVAC system. The end result? Higher utility bills as your HVAC system struggles to draw power and circulate clean air.

Read: Return Air Duct – What Is It And What For?

3. Increases the Likelihood of Damage

Blocking cold air return vents can cause the AC coils to freeze over time. These frozen air conditioner coils damage the system, slowing it down and making it work overtime. The blockage places a lot of stress on the HVAC due to the unregulated airflow.

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These problems are expensive and may require frequent fixes from a professional. You may also need to replace a few parts if there are cracks or breakage, and this can cost you heavily in the long run.

How To Avoid Blocking Cold Air Return Vents?

Being wary of your furniture placement and replacing the filters regularly will help to prevent blocking these vents. Most of the time, people don’t intentionally block these airways; it’s usually due to how your room is set up. As such, it’s crucial to ensure you don’t accidentally block the vents while rearranging your room. 

Let’s say you have a small to medium-sized room with multiple pieces of furniture lying around. Keeping these objects in the right places will help free up more space for the vent to suck in warm air and use it to run the HVAC. If you have chairs, sofas, or couches near the air vents, ensure they’re kept away from the opening.

If there are curtains in your room, try to ensure the bottoms are above the vents or they may cover the air vent and can disrupt airflow. The same goes for rugs—if there are rugs lying around, keep them and other furniture a few feet away from the vents. If you’re working with a smaller room, it’s easier when there are fewer objects to move around.

It’s best to regularly call an HVAC technician to check the vent grills for any issues. Bi-monthly or monthly checks are essential to keep your vents dust-free and clean. You also want to clean your filters from time to time as clogging can disrupt the airflow inside the vent. Consider replacing the filters from time to time if possible.

Read: Do You Have To Vent A Portable Air Conditioner In Heat Mode?

Benefits of Keeping the Cold Air Return Vent Open

We know how blocking a cold air return vent can be detrimental. But what are the benefits of leaving these vents open?

Makes Your HVAC System Efficient

Air vents are the backbone of an optimized heating and cooling system for the house. Blocking them will hinder the system in its job of keeping your home at a comfortable temperature. When left open, these air return vents make your home feel refreshing, airy, and calm throughout the day. They also keep the HVAC system running smoothly and with fewer issues.

You Save Money

As discussed before, an efficient HVAC system will help you save more money in the long run. These systems are optimized to keep your room warm or cold, depending on your needs. The cold air return vents suck in hot air, purify it, and let it out through the AC vents. The system uses a certain amount of power to perform this function.

However, a blocked vent means your system needs to strain harder to circulate air, for which it will draw more power. As such, it’s best to leave cold air vents free so you can avoid this problem and prevent your electricity bill from rising.

Helps Maintain the Right Air Pressure

Cold air return vents help to maintain the right air pressure inside your home, ensuring that clean air is constantly circulating throughout the premises. The circulating pump inside the HVAC system works by

  • Utilizing the sucked-in air from the air return vents
  • Turning it into hot or cold air depending on the setting
  • Distributing it to the house through the heating or cooling system

By repeating this process over and over, the HVAC system ensures your home is cozy and set to the right temperature. It also ensures that stale air is constantly removed from the premises by regulating pressure and allowing the free flow of air. 

Read: Why Furnace Blowing Cold Air? – Troubleshooting Guide

Keeps Away Allergens

Active and open air vents prevent the entry of pollen and dust particles into your rooms. They help keep the air fresh by constantly circulating it through a filtering system, ensuring there are no pollutants in the air space. 

Leaving the cold air vents open also ensures that pollen and dust don’t settle and clog the filters, which could cause the particles to recirculate within the house. And if you’re someone with allergies, keeping the return vents open is an effective way of preventing an adverse reaction.

Read: How To Reset Air Conditioning Unit?

Final Thoughts

So, to keep a clean air space within your home, ensure that your cold air return vents aren’t blocked. Blocking them will make the other parts work overtime, heat up, and get damaged in the long run. Sometimes they can get unintentionally blocked due to furniture or other elements in the room, and it’s crucial to be wary of this.

So, try out the tactics outlined in this article to keep your return air vents clean and functional.