How can I improve my cold air return?

Author: Mack Lakin  |  Last update: Wednesday, October 1, 2025

Down Low: if you have your air return lower on your wall it will function better as a cold air return. This will allow your air return to draw in cold air as it sinks to the bottom of the room. Making it more efficient at recirculating this cold air through your furnace to repeat the heating cycle.

Why is barely any cold air coming out of my vents?

If your HVAC system is blocked up or clogged somewhere, your AC won't send enough cool air through the vents when it's running. A fan problem can also cause this issue. Or, you can end up with that problem if you don't address the circulation issues. It's not always easy to realize a circulation problem in the summer.

Can I put a filter on my cold air return?

Putting filters in air return vents is generally not recommended for several reasons: Airflow Restriction: Return vents are designed to allow air to flow back to the HVAC system. Adding filters can restrict airflow, leading to reduced efficiency and potential strain on the system.

How to fix not enough return air?

To fix this, you could look at enlarging the existing return grill or adding an additional return grill. You would need at least another 176 square inches of free space or roughly 270 square inches of filter space. So something like a 14x20 should put you at that threshold.

Is it OK to cover up a cold air return?

Don't cover your return unless your certain that your furnace/AC doesn't need the extra cfm to operate. Your air handler/furnace can only supply the amount of air it can pull to it through the return.

Learn about Cold Air Returns & Heat Runs - DIY

What happens if you don't have enough cold air returns?

A lack of return air can cause your HVAC system to overheat, leading to frequent shutdowns or overheating warnings. This overworking can also result in the air conditioner blowing warm air, especially in high temperatures.

How to increase airflow to the second floor?

How to Increase Airflow to Second Floor?
  1. Keep Air Conditioner Running in Fan Mode. ...
  2. Install a Ceiling Fan. ...
  3. Increase the Size of Return Vents. ...
  4. Increase Number of Vents. ...
  5. Clear the Vents. ...
  6. Close Vents on Lower Floors. ...
  7. Go for Ductless Air Conditioning. ...
  8. Get a Zoned HVAC System.

How do you increase cold air return?

One way to help combat this problem is to modify your cold air return ducts for better airflow. Whenever possible, expand your existing ducts vertically by cutting out pieces of wallboard and installing a new cover and air filter to fit.

How do you fix a weak air flow?

To resolve weak airflow issues, it is recommended to: check and replace air filters regularly. clear any obstructions near vents or registers. inspect and maintain the blower motor.

Does oversizing a return air system cause problems?

Due in large part to the short cycling issues mentioned above, components on an oversized heating and/or air conditioning systems are more likely to fail sooner than those on a properly sized system. As a result, you may end up having to replace your HVAC system sooner than expected.

Is it OK to partially block a cold air return?

You should never block your air return vents. Period. However, if you're looking to keep your home cooler in the summer, you can try closing lower supply vents and keeping upper ones open, allowing cooler air temperatures to come in from above and sink throughout your house.

How many return vents should a house have?

Instead, there should be at least one return vent in every room, with two or three being ideal. If your house has only one return vent, this is not a problem — make sure to keep the doors open in every room so the air can circulate properly. Make sure there are no furniture, draperies, rugs, etc. blocking return vents.

Is there a return air filter?

As the air gets sucked into your return vent, the return vent filter blocks out dust and particles from entering the airstream to your HVAC unit. Return air vent filters are sometimes preferred over using a filter in the HVAC unit for these reasons: Filters in return vents prevent dust from getting in your ductwork.

How do I increase air flow to my vents?

If you want to increase airflow in a room without affecting other rooms, here are our top recommended solutions.
  1. Open the windows and doors to the room. ...
  2. Enlarge the return vents. ...
  3. Ensure you clean the HVAC air cleaners. ...
  4. Close the vents to some rooms. ...
  5. Use a fan. ...
  6. Unblock the vents.

Why is my AC not as cold as it should be?

If your AC is cooling but not working properly, it could be due to issues like a clogged filter, low refrigerant, or a malfunctioning thermostat. Other possibilities include a faulty compressor, dirty coils, or blocked vents, all of which can affect the system's performance.

Should return vents be open or closed in winter?

Conversely, in the Winter heating season, you will want to pull the coldest air back to the furnace to be warmed and create circulation. In these months, you'll want the lower air return open and the upper air return closed.

Why can I barely feel air coming out of my vents?

Lots of things can cause your blower to have trouble, especially if it gets too dirty. A fan clogged by dirt, a stuck wheel, broken motor, or a loose fan belt are all common problems that reduce the amount of airflow you feel coming from your vents. How to fix: Call an AC tech to examine and fix the blower.

How to clean coils in AC?

Check your air conditioner warranty before cleaning.
  1. Turn off the AC and shut off power to the condensing unit. ...
  2. Remove outer case and caging. ...
  3. Clear out debris and broken fins. ...
  4. Spray out the unit. ...
  5. Dilute 1-part Foaming Coil Cleaner with 3-parts water. [ ...
  6. Apply cleaner to coils.

How do I know if my cold air return is blocked?

Common Issues with Return Ducts: Clogs and Leaks

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.

Do duct booster fans work?

A duct booster fan improves airflow in HVAC systems by pushing air through ducts, ensuring every room receives proper heating or cooling. It's akin to giving a gentle push-to-air movement. However, their effectiveness depends on proper installation and addressing any existing HVAC system issues.

How do you get cold air to circulate?

Use Multiple Fans

When planning out how to circulate air with fans, look for opportunities to create a network of circulators throughout the house to work the naturally colder air in some places out to other areas of the house that collect heat.

Why is my AC not blowing cold air upstairs?

If you're facing this issue, there could be several reasons for it, including outdated air conditioning systems, blocked vents, dirty filters, leaking air ducts, or inadequate insulation.

How to fix air flow problem in house?

Check your vents to see if they are not obstructed in any way. Remove any furniture or drapes blocking the airflow. While you are checking all the vents in your home, take a piece of cloth to clean the dust off the vents' grills. Fix any leaks and holes in your HVAC ductwork.

How to force cold air upstairs?

Simple Fixes to Help Cool Your Upstairs
  1. Properly open vents, don't block the return air supply. Let the air flow! ...
  2. Install lightly colored curtains or drapes. ...
  3. Keep heat-generating appliances off. ...
  4. Run a fan (when you're in the room) ...
  5. Keep your HVAC fan set to 'on' ...
  6. Inspect your ductwork. ...
  7. Check your insulation.

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