You will need about 8 returns for 1600 cfm/4 ton cooling.
The earliest HVAC systems featured a large, single return vent placed somewhere in the middle of the home, but this is not the most effective system. Instead, there should be at least one return vent in every room, with two or three being ideal.
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.
The general guideline used when calculating the amount of Freon in a residential A/C unit is 2-4 pounds per ton of cooling.
Size of the HVAC Unit
Most air conditioners range between 1 and 5 tons. Since an air conditioner uses an average of 2 to 4 pounds of refrigerant per ton, a 3-ton AC will need an average of 9 pounds.
Residential Air Conditioner Freon Refill Cost
Most homeowners will pay in the range of $200 to $400 for a refill, depending on the type and size of their HVAC unit. If you own a larger r22 unit, you may have to spend $600 or more. To break this down for you, a 25lbs unit of r410A costs anything between $100 and $175.
Can You Have Too Much Return Air? Too much return air coming through your system isn't much of an issue because the fans and ductwork working to get that air back into the system only pull with so much force to make the HVAC system work correctly.
If there's not enough return air, your living room can be 10℉+ warmer or cooler than, for example, the bedrooms. Not enough return air in summer can cause rooms close to the central unit to be cooler and those farther from it to be warmer. In winter, rooms farther from the furnace can be too cool.
While return vents don't always require filters, adding them provides additional filtration, improving indoor air quality and keeping dirt and debris out of your system. However, there are pros and cons to consider.
The cost of a 4-ton AC unit typically ranges between $4,000 to $5,500. However, this price can vary depending on factors such as the brand, model, energy efficiency rating (SEER), and additional features like advanced filtration systems or smart thermostats.
The largest residential HVACs generally available are 5-ton units (ton here refers to cooling capacity, not the actual weight of the unit). If your house is so large that it would need six tons or more to effectively cool it, then you'll need to install two or more units.
You will need about 8 returns for 1600 cfm/4 ton cooling.
Start by setting your thermostat higher than normal when you are away, and at 78 degrees when you are home. That is the Department of Energy's recommended setting when you need cooling, but want to save energy.
Return registers can be large and centrally located in your home, or they can be in every room. HVAC professionals recommend that each room have a cold air return vent to help with flow and temperature control. These vents are typically found on an interior wall.
Blocked or insufficient return air can lead to reduced airflow from your vents. Symptoms include weak airflow and uneven cooling or heating throughout your home, with some rooms feeling much cooler or warmer than others. Homeowners should regularly check vents for consistent airflow.
One per room is ideal, but placing two or three in central locations can provide enough air circulation to maximize the energy efficiency of your HVAC and optimize indoor air quality, so your family stays healthy. If your home has multiple stories, you should have at least one return air vent per floor.
Does Every Room Need Air Return Grilles? 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.
The Secret to Comfort is Balanced Airflow
The current Supply Air vent pressurizes the room, until (in many instances) the pressure inside the room slows the airflow coming from the Supply Air vent! When we install the Return Air vent, the pressure is alleviated. The Return Air vent balances the Supply Air vent.
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.
If you have a combined heating and cooling system and need to decide between placing the return vents high or low, consider your climate. If you live in cooler climates, it might be wise to install them towards the floor, whereas if you reside in warmer areas, they should ideally be installed close to the ceiling.
Each make and model of air conditioner needs a slightly different amount of AC refrigerant. According to PG&E, most central air conditioning systems use two to four pounds of refrigerant per ton of cooling capacity.
A Question of Supply and Demand
Therefore, maintenance people and air conditioning system specialists have less supply and are charging more for it. Some businesses have even reported thefts targeting their Freon canisters thanks to its newfound value. After 2020, R-22 won't be produced at all in the United States.
You can save about $100 in labor costs by doing the car ac recharge job yourself. Stop at any auto parts store and pick up an R-134a A/C recharging kit. I used the A/C Pro Recharge Kit product because it came with a reusable gauge and a quick-connect fitting, and the refrigerant contained a seal conditioner additive.