What size should my air return be?

Large Returns A typical supply vent is 4 by 10 to 12 inches and a typical return vent is 16 by 20 inches or larger. Houses often have two or more return collecting points, each with a filter, which join before re-entering the heating unit.

What size should the return air grill be for a 4 ton AC unit?

Calculate the square root of the total. (Example: 4 (ton unit) x 144 square inches = 576 squared. The square root of 576 is 24. Therefore, your return air duct and grill size will be 24 by 24 inches.)

Can a return air duct be too big?

Can an air return be too big? No, an air return cannot be too big, except in extreme cases where a closed room is temporarily under negative air pressure. Return vents maintain air pressure, filter out debris, and are critical to the efficient operation of any HVAC system.

Can you have too much return air?

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.

What size should the return air grill be for a 5 ton AC unit?

x 25-in.
x 25-in. Return grilles are the best choice for a five-ton system in order to deliver 2,000 cfm back to the blower without causing the return to hemorrhage.

Can air return too big?

How high should a cold air return be off the floor?

In the upper stories of the house, the return air duct openings on each floor should be approximately equal to the sum of the hot air outlets. In the basement, to avoid chimney backdrafting, the return air duct should be only half as large as the sum of the hot air ducts.

What is a return air 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. When an HVAC system delivers air to a room, it increases that room’s air pressure. Return vents exist to remove the extra air.

Can return air be too small?

If the return duct is too small, there are an inadequate number of return grilles or they are undersized, it can’t return enough air to recirculate back into the system. This poor airflow not only makes your system run longer than necessary to provide comfort, but increases your energy bill as well.

Can flex duct be used for return air?

Flex duct doesn’t come in an R12 version, so you will have to wrap it. Its fine to use for a return.

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. If not enough air is brought back, your HVAC system will not be able to keep up with temperature demands. In some cases, two returns may be necessary to provide enough return air.

What size return air vent?

There usually are fewer return vents, but they are much larger. A typical supply vent is 4 by 10 to 12 inches and a typical return vent is 16 by 20 inches or larger.

How important is the return air grille?

A return air grill will cover such ducts, and can also act to regulate the flow of air . They also act to close off the ducts from view. A return air grill also has a filter mounted on it to trap particulate matter and thus ensure that the recirculated air is more pure. This can also in the long run reduce the amount of cleaning required for ducts.

What is an air grill?

A standard air grille is a flat metal vent attached to a wall or floor of a building. This grille protects the air ducts of the ventilation system from rodents and objects. Most air grilles are made from a lightweight metal material and are typically painted white.