AABC Test and Balance Engineer (TBE) case studies
AABC Test and Balance Engineer (TBE) · Put your knowledge to work in context.
The Test and Balance Engineer (TBE) credential is a professional certification for technicians and engineers who commission, adjust, and document air and water systems in buildings. It signals that a practitioner can measure airflow, set hydronic balance, verify pressurization and ventilation, interpret controls, and deliver defensible field reports. The AABC Test and Balance Engineer (TBE) case studies are 5 cases and about 2,691 words.
1Economizer Damper Hunting on a Packaged Rooftop Unit
A 40-ton packaged RTU with factory DDC serves a single-zone assembly hall. The TAB firm is called back two weeks after final balancing.
530 words, about 3 min2Pitot Traverse Uncertainty in a Short Rectangular Duct
A TAB technician must measure airflow in a 24 in × 18 in rectangular supply duct serving a critical cleanroom. The only accessible straight run is 3 duct diameters downstream of an elbow and 1.5 diameters upstream of a transition - well short of the recommended 7.5/2.5.
497 words, about 2 min3Hydronic Loop That Won't Balance - Pump Curve vs. System Curve
A new 12-story building has a primary-secondary chilled water system. The secondary loop serves 30 fan-coil units through a reverse-return header and a variable-speed secondary pump.
506 words, about 3 min4Building Pressurization Conflict Between Lab Exhaust and Stair Pressurization
A research building has 20 fume hoods on floors 2–5, a dedicated lab exhaust fan, and a stairwell pressurization system for the egress stairs. During a fire-alarm test, the stair pressurization fan ramps up and the building's main entrance doors become very hard to open - a technician measures roughly 45 lbf to crack the door.
589 words, about 3 min5Disputed Final Report After a Change Order
A TAB firm completed balancing on a 200,000 sq ft office building. Two weeks before substantial completion, the owner's contractor added 14 new VAV boxes on floor 4 under a change order that was never issued to the TAB firm.
569 words, about 3 min