Fume Hood Control System

1
Fume Hood Control System

• Conditions
• 45 year old facility
• 3 laboratory wings (50,000gsf/wing)
• 50 fume hoods per wing
• 50 individual exhaust fans ½ -1hp

2
Original Fume Hood Exhaust Stacks
3
Original Exhaust Fans
4
Fume Hood Control System

• Problem
• Installing fume hoods w/o increasing make-up air
• Negative in-balance grew to 15 to 20,000 cfm/
  wing
• Safety problems (air handler shutdown, exit doors
  opening

5
Fume Hood Control System

• Solution
• Two alternatives
• Air handler/s
• Fume hood control system

6
Fume Hood Control System

• Solution
• Costs were very close for either option (600,000
  per wing)
• Difference
• Air Handler (20,000 cfm) increased Facilities
  operating costs loads on chillers boilers
• Fume hood controls reduced Facilities operating
  costs loads on chillers boilers, saving
  approximately 80,000/yr

7
Fume Hood Control System

• Solution
• Fume hoods operate _at_ 100 fpm Face velocity _at_ all
  times
• Sash movement adjusts air changes from 10-15 full
  open position, 4-6 in closed position
• Example 6 foot hood takes 1200 cfm w/sash open,
  cuts back to 200 cfm w/sash closed

8
New Fume Hood Exhaust
9
New Fume Hood Exhaust Fans Plenum
10
New Fume Hood Exhaust Fans Plenum
11
New Exhaust w/Damper Control