Hvac Duct Sizing Chart

Select suitable velocities for main and branch ducts from the table below.

Hvac duct sizing chart.

While a duct sizing calculator built for a specific type of ductwork is the best possible method for sizing ducts the attached chart can be used in most single story homes with a centrally located unit and reasonable length duct runs. Most technicians are skeptical about these numbers especially on the return air side of the system. This equal friction method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications. If a room is 250 square feet the result will be a duct size of 8 inch round.

Pdh online pdh center 5272 meadow estates drive fairfax va 22030 6658 phone fax. Hvac calculations and duct sizing 2012 instructor. Residential duct sizing guide the following duct sizes are based on a fraction drop of 10 inches per 100 feet of lineal duct. Duct system sizes and airflow quick chart created date.

1 and the charts below. Find the sizes of main and branch ducts from the air flow rates and the velocities by using eq. The method can be summarized to. The velocity reduction method can be used when sizing air ducts.

You can also do this by checking for them online or by using a manual that is sold by distributors. Field duct sizing chart rectangular sheet metal duct 07 on most metal duct calculators step one identify the volume of air that will be passing through the duct step two select the duct size from the table that can carry that volume of air step three if desired airflow exceeds the cfm rating increase to the next duct size. Step 4 determine the cubic feet per minute and duct sizes for all the rooms. Flex duct 05 on most metal duct calculator round metal pipe 06 on most metal duct calculators field duct sizing chart rectangular sheet metal duct 07 on most metal duct calculators duct size duct height net inside dimension in inches round duct size estimate.

Larger volumes or higher static pressures should be dealt with on an individual.