Rev Up Your Vav

Engineered Systems, Jan, 2000 by Steven Angle

Angle, PE is a facilities engineer at Rensselaer Polytechnic Institute (Tray, NY).

     Number of deficiencies discovered during commissioning of over 500
                                VAV boxes.
                     Installation verification results
3  Ductwork supports incorrect
4  Missing t-stat
18 Incomplete insulation
18 Missing balancing valve
44 Incomplete/incorrect labeling
24 Drain valves not capped
1  Access doors missing
5  Air bleed vent hidden/bad location
2  Access door blocked
8  Poor access to components
1  HW control valve not accessible
8  Bad location of t-stat
7  t-stats too close to each other
7  Not enough straight duct
1  VAV box upside dawn/backwards
8  Missing strainer
                         Functional testing results
Control Problems
3                Control tuning constants or span wrong
9                Control air not connected
5                Max. cfm setting wrong
7                Software locked in full cooling
5                Control valve head loose/missing
5                Control valve action reversed
8                Software program not working
4                Software displays wrong airflow
2                Software locked reheat valve closed
1                Software interlock not programmed
3                Zero airflow, software locked damper
14               Reheat valves limited to [less than]100%
                 stroke
Other Problems
1                Broken airflow sensor line
6                Pneumatic line stops diaphragm
3                High air noise, insulation required
2                t-stat off by 2[degrees]F
9                Damper faulty
11               No/low reheat water, manual valve
25               Can't reach design airflow
1                Reheat valve stuck, no control
4                Broken t-stat
1                Air leaks through t-stat
288 Total number of deficiences