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2. FITTING EQUIVALENT LENGTHS
- Flex pipe equivalent length is
smooth pipe x2
- Flex fitting equivalent length is
smooth fitting x2
- 45º perimeter pipe elbow
equivalent length = 5 ft. (1.52 m)
NOTE
: Where flex duct is used
to make 45º elbow
equivalent length =
10 ft. (3.0 m)
- Y-equal sides
equivalent length = 10 ft. (3.0 m)
- Y-Side branch
equivalent length =
35 ft. (10.7 m)
- Round plastic diffuser
equivalent length = 100 ft. (30.5 m)
NOTE
: Maximum airflow assumes
diffuser is in full open position.
- Tee take-off
equivalent length =
50 ft. (15.24 m)
- Angle boot
equivalent length = 30 ft. (9.14 m)
- 90º perimeter pipe elbow
equivalent length = 10 ft. (3.0 m)
NOTE
: Where flex duct is used
to make 90º elbow
equivalent length = 20 ft. (6.1 m)
- Round wall cap spring
damper or screen
equivalent lengths =
60 ft. (18.29 m)
- Wall grill 50% free area
equivalent length = 15 ft. (4.6 m)
- Increaser/Reducer
equivalent length
= 8 ft. (2.43 m)
