Insufficient return air can lead to higher energy bills. When your HVAC system doesn't receive enough return air, it must work harder to maintain the desired temperature, increasing energy consumption. Homeowners might notice a spike in utility costs without a corresponding increase in usage.
Having a number of return vents (preferably one in every room, but also 2 or three is far better than just one) creates regular air pressure. If you have one return vent, your house is great. Maintain the doors to every room open so air can properly flow.
Undersized return ducts can cause up to 20% of the conditioned air in your home to escape. This occurs due to air pressure and not a hole in a duct. The excess pressure is caused by exhaust air staying in a room longer. The room may become uncomfortable and stuffy.
From dirty air ducts, blocked damper valves, damaged duct runs, to an insufficient numbers of return air vents, there are a variety of signs that may indicate a furnace air flow issue in your home.
❄️ Solutions to Improve Return Air
Homeowners should clean filters, check vents for blockages, and ensure vents are open and unobstructed. Routine maintenance tasks help maintain optimal airflow and system efficiency, preventing common return air issues.
Common issues like leaks, disconnections, or obstructions within the ducts disrupt the flow of cooled air, causing rooms farther from the HVAC unit to suffer the most. In some cases, inadequate insulation of ducts can allow heat to infiltrate, further exacerbating the problem.
If your boiler or furnace is in an enclosed space and relies on indoor air for combustion, you run the risk of incomplete combustion, which produces toxic byproducts like carbon monoxide.
Replace Furnace Filters
Replacing dirty filters is an easy way to improve airflow in your home. Air filters are inexpensive and can significantly impact your home's comfort. They're also easy to install, so there's no reason not to have them in your home.
While furnaces can stop operating for complicated reasons, home owners should check a few usual suspects first behind a lack of hot blowing air: Electrical problems causing a loss of power. Blocked air vents and ducts restricting airflow. Improperly configured thermostat settings.
Low airflow can make your ears hurt in one room compared to another. Use a barometer to measure the pressure in the kitchen, living room, bedroom, and other rooms in the house. If you notice different pressure measurements throughout the house, this is a sign there's not enough return air.
If you are installing just one or two return vents, you will want to go with a 12-inch return for 2-ton units and lower. 14- inches for 3 and up. 16-inch should be suitable for 4 ton systems, whereas 5 might require 18-inch returns.
Dirty filters, leaky ducts, and poor insulation can cause cold return vents. Leaky ducts often cause cold air to blow even after cranking the heat up. 20-30% of air, especially hot air, is lost because of leaky ducts. Cracked, holey ductwork needs sealing or replacement.
However, most HVAC contractors use a rule of thumb to determine the number of air vents needed. For example, for a standard residential HVAC unit, you'll generally need one supply vent and one return vent for every 100 to 150 square feet of living space.
If the return duct is too small or there are an inadequate number of return grilles, your HVAC system won't be able to return enough air to recirculate into the system. Again, it's like if you were breathing in through a straw while jogging.
Adding a return air vent will cost homeowners $350 per vent on average, depending on the vent size and duct material. A professional can assess the right duct material you need for your home and can give you an accurate estimate.
This can be caused by a loose fan belt, or a dirty motor. Solution: First, clean the blower fan and the area around it. It has to deal with a lot of air, so it naturally becomes dirty over time. If that doesn't fix it, the fan belt probably needs to be replaced.
Add or remove supply and return ducts to deliver enough air to each room. Seal or insulate accessible under-insulated ducts. Add dampers to the ducts. This directs the airflow coming from the HVAC unit and shifts the desired amount to each room.
So why can one room in your home be colder than others? Blocked or Covered Vents: One of the most common reasons for a cold room is blocked or covered vents. Heavy furniture or objects placed in front of vents can obstruct the flow of warm or cool air.
When temperatures drop below zero or even below freezing for extended periods of time, sometimes your furnace can't keep up. If your home is not heating up to the temperature you've set, try lowering it a few degrees. The temperature of the air coming out of your vents doesn't get warmer by turning up your thermostat.
In most cases, your HVAC system does not pull air from outside when it is heating or cooling your home. Instead, it recirculates the air inside your home. This means it takes the air from inside your house, heats or cools it, and then sends it back into the rooms. However, there are exceptions.
There are several potential reasons why one room may be significantly warmer than the rest. These can include inadequate air flow, poor insulation, or even the placement and size of the AC unit. It's also important to consider external factors such as sunlight exposure and window efficiency.
You can usually spot return vents on your walls, ceiling, or floors. Look for a white grille without shutters to spot an air return vent. These vents will typically integrate seamlessly into your home.
One of the primary reasons for a hotter indoor environment is poor insulation. Inadequate insulation allows heat from the sun to penetrate your home, raising the overall temperature. Areas such as attics, walls, and floors that lack proper insulation can contribute significantly to this problem.