1.3 Field Verification, Pre-TAB Readiness, and Deficiencies

Preliminary Inspection, Readiness, and Deficiencies

Readiness determines whether the measurements are valid

TAB is performed on an installed system in a defined operating condition. Loaded construction filters, clogged strainers, missing ceiling tiles, closed life-safety dampers, reversed rotation, incomplete controls, or an unfilled hydronic loop can create readings that become obsolete as soon as the condition is corrected. The preliminary inspection identifies those conditions before final balancing.

Use the project readiness checklist, approved documents, manufacturer startup requirements, and the applicable NEBB procedure. The CT verifies observable conditions and records evidence; the responsible installing, controls, electrical, or commissioning party completes work outside the CT's authority.

Document and architectural checks

Confirm current drawings, schedules, approved submittals, control sequence, equipment-startup records, and design values are available. Walk the actual system and reconcile tags. Identify inaccessible devices, missing test ports, unsafe access, and changes not shown in the documents.

For air systems whose performance depends on the building enclosure or ceiling return plenum, check the specified test condition: exterior openings, access panels, ceiling tiles, shafts, and major penetrations. The requirement is not that every construction detail on every project be complete; it is that the tested boundary match the project-defined operating condition and that material deviations be recorded.

Air-side readiness

Inspect the air path from intake through terminal and return or exhaust. A useful sequence is:

1. verify fan and motor tags, physical condition, guards, rotation, drive alignment, and authorized speed range;
2. verify specified filters are clean and correctly installed and coils are reasonably clean;
3. inspect access doors, flexible connections, duct damage, leakage evidence, and obstructions;
4. confirm balancing dampers are accessible and life-safety devices are in the commanded test position without forcing them;
5. verify terminals, grilles, diffusers, and return paths match the design; and
6. confirm supply, return, relief, exhaust, and outdoor-air controls respond in the required mode.

A centrifugal fan rotating backward can still move air in the normal duct direction. Low flow, low pressure, or abnormal current may suggest the condition, but verify rotation directly against the equipment arrow using an authorized safe method. Qualified electrical personnel perform lead changes after de-energization and verification.

Set belt tension by the drive or belt manufacturer's force-deflection procedure. A geometry such as 1/64 inch deflection per inch of span, when specified, only identifies test displacement; the required force still comes from manufacturer data.

Hydronic readiness

Verify system type, fluid, temperature, fill condition, air removal, valve lineup, control mode, pump rotation, and stable operation. Confirm strainers or temporary screens were inspected or cleaned under the startup procedure and establish a clean baseline when possible. Do not prescribe a universal strainer differential or assume a high reading has one cause.

Check that pressure/temperature ports and calibrated flow devices are identified, accessible, capped, and within instrument pressure and temperature limits. Confirm the expansion-tank connection and makeup system are in their approved condition. Required high-point residual pressure comes from the design and equipment requirements, not an automatic four- or five-psi rule.

Control valves, three-way valves, bypasses, and variable-speed pumps must be placed in the specific test mode. “All valves open” is not correct for every topology. Record all overrides and arrange restoration.

Electrical and control readiness

Only qualified authorized personnel perform energized measurements. Record nameplate voltage, phase, FLA, speed, and drive limits. Verify all three voltages and currents when the task requires them. Do not use 2% voltage unbalance as a universal safe maximum; apply manufacturer and applicable motor guidance and escalate abnormal results.

At the BAS, confirm sensor values are plausible, actuators stroke, safeties remain active unless an approved test specifically addresses them, and the commanded mode matches physical operation. A graphic command is not proof of damper or valve position.

Deficiency handling

A deficiency record should include:

• device and exact location;
• date, operating mode, and observed condition;
• measured value and design or expected value;
• instrument or observation method;
• effect on testing or acceptance;
• photographs or drawing references when useful; and
• notification and disposition status.

Use factual language: “FSD-2 remained closed at a 100% open command; no supply flow was measurable downstream” is stronger than guessing at a failed transformer. Hold affected final testing when the condition makes results unsafe or invalid. Never force a life-safety device, bypass an interlock, fabricate an inaccessible result, or repair another trade's work without authorization.