The air flow rate of a 3-ton heat pump is roughly 1200 cubic feet per minute. To determine the size of the filter grill, divide the airflow rate (CFM) by two. One filter grill, or the total area of all grills, must have a surface area of at least 600 square inches in order to provide the system with the air it requires to function properly.
How big should my return grill be?
To get the size of the return air grille, multiply the CFM of the HVAC unit by 350 to get the grille area in square feet (measured in square feet). After that, increase the grille area by 144 to convert it to square inches in the metric system. The next step is to select your ideal grille size that corresponds to the needed grille area.
How big should return air vents be?
Exceptional Profits Return vents are often found in less numbers, although they are significantly greater in size. A common supply vent measures 4 by 10 to 12 inches in size, whereas a typical return vent measures 16 by 20 inches or greater. Typically, houses have two or more return collecting points, each equipped with a filter, which are connected before returning to the heating unit.
How much return air do I need per ton?
There is no such thing as too much return air; as an HVAC contractor, you should aim for no less than 144 square inches per ton of air. In regards to the 3.5 TON vs. 4 TON comparison, Given that the average square foot per ton is 400, if the house is 1600 SQFT, a 4 TON unit should provide adequate cooling.
Can a return air duct be too big?
Return air is never enough, and as an HVAC contractor, you should aim for a minimum of 144 square inches per ton of air conditioned space. 3.5 TONS Vs. 4 TONS: Which is Better for Your Business? Given that the average square foot per ton is 400, if the house is 1600 SQFT, a 4 TON unit should be plenty.
What size return do I need for a 3.5 ton AC unit?
Electric heat pumps must be tested in line with UL 559 or UL 1995 standards before being installed. As an illustration, consider a 3.5 ton heat pump. The ductwork for this system must be sized in accordance with the rule of six square inches of clear duct space per 1000 BTU of cooling. 12,000 BTUs are contained in each ton of cooling fluid.
What size return do you need for a 5 ton unit?
25-in. x 30-in. When designing a five-ton system, return grilles are the best option for delivering 2,000 cubic feet per minute (cfm) back to the blower without causing the return to bleed.
How big of a return do I need?
Simple divide 980 cubic feet per minute by 400 cubic feet per minute per tonne to get the size of your tonnage. This will result in a tonnage of 2.45 for this particular spot. Using the rounding rule, we arrive at a tonnage value of 2.5. A return air grill should be designed for air speeds ranging from 300 to 500 feet per minute (FPM) (feet per minute).
What happens if there is not enough return air?
Simple divide 980 cubic feet per minute by 400 cubic feet per minute per ton to get the approximate size of your tonnage. This will result in a tonnage of 2.45 for this particular area. Because we always round up, our tonnage value is 2.5. It is recommended that a return air grill be sized for air speeds ranging from 300 to 500 feet per minute (feet per minute).
What size should the return air grill be for a 4 ton AC unit?
4 (ton unit) × 144 square inches = 576 squared (as an illustration). The square root of 576 is twenty-seven. As a result, the return air duct and grill will measure 24 by 24 inches.)
How many vents should a 2.5 ton AC unit have?
To move the 1000 CFM required for a 2.5 ton system (about 400 CFM per ton), two 14″ flexible return ducts or one extremely short flexible 18″ duct would be required for the 2.5 ton system to carry the 1000 CFM.
Should return duct be same size as supply?
To transport the 1000 CFM required by a 2.5 ton system (about 400 CFM per ton), two 14″ flexible return ducts or one extremely short flexible 18″ duct would be necessary for the 2.5 ton system to operate properly.
Do I need more return vents?
Having many return vents (preferably one in each room, but even two or three are preferable to one) helps to maintain consistent air pressure throughout the house. If your home only has one return vent, everything is OK. Keep the doors to each room open to ensure that air may flow correctly.
Can flex duct be used for return air?
Flex duct is a type of return air duct that is extensively utilized in commercial air conditioning systems. The flexibility of the duct allows it to endure a certain amount of negative pressure from the return air. A flexible duct, when constructed properly, may be a very dependable and convenient method of ducting installation. Because of airflow concerns, flexible duct is typically given a negative reputation.