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Airside procedures
1. All related HVAC and exhaust air system should be operating.
2. Determine whether any other HVAC or exhaust air system could affect the system
Ready to be balanced,
3. Make Pitot tube traverses on all main supply and major branch ducts where possible
to determine the air distribution. Take extreme care that there is no damage to hepa
filters by debris being pulled or pushed into them.
4. Adjust balancing dampers of each major branch duct that is high on airflow. A
minimum of one branch duct-balancing damper shall remain fully open.
5. Measure and record the airflow of each terminal device in the system without
adjusting any terminal outlet. Flow measuring hoods are the preferred airflow-measuring
device.
6. The total airflow for the terminal outlets should be close to the Pitot tube traverse air
measurement of that branch, and the main duct traverse air measurement should be
within10% of the total of all terminal outlet air measurements.
7. Check for excessive duct leakage if total terminal outlet air measurements are less
than95% of the main duct traverse air measurements.
8. Adjust the terminals that are highest on airflow to about10% under design airflow.
9. Next, adjust each terminal outlet throughout the zone or system to design airflow and
record measurements and make any necessary branch damper adjustments.
10. An additional adjusting pass throughout the system may be necessary. Make final
adjustments to the fan drive where required. Record all data.
11. Adjust terminal device vanes to minimize drafts and for proper air distribution.
12. Measure and record system static pressures.
13. Measure and record all required outdoor air, return air, mixed air, and supply air dry
bulb a wet bulb temperatures. Measure and record all plenum static pressures.
14. Measure and record all coil entering air and leaving air dry bulb and wet bulb
temperatures. Measure and record all coil pressure differentials.
15. Measure and record final fan motor full load amperages and voltages.
16. If the airflow is low, proceed with a proportional balancing. Proportional balancing
is purporting the air equally by dividing the total airflow by the design airflow to get the
percentage of airflow. Then multiplying the percentage of airflow to the design airflow for
the percentage of air to set to.
Waterside procedures
1. Continually check system and vent air from high points and circuits with lower flows
during hydronic balancing. Periodically check and clean strainers.
2. Using “pump shutoff head,” verify each pump head, operating curve and impeller size.
3. Adjust pump to design flow and record data.
4. Adjust boilers and or chillers to design flows and temperatures and record data. If the
Pump is pumping water to coils first start there, always fallow the piping.
5. If flow-measuring devices are used, record the flow data throughout the system before
adjusting the system.
6. Measure and record pressure drops through all coils and or units. Compare with
submittal data for high and low flows.
7. Adjust high flows to near design.
8. Adjust pump flow to design and check pressures, amperages and voltages.
9. Set bypass balancing cocks to90% of maximum flow through coils that have threeway
control valves.
10. Repeat the above procedures until all coils and units are operating within10% of
design. When coils in parallel are above five coils, balance the coil nearest to the pump
to the coil at the end of the piping. The first coil is set at80% to85% of design flow
depending on the number of coils; increase the percentage equally for each coil to the
end of piping, then check the first coil flow.
11. Measure and record final pump pressure, amperages, and voltages.
12. Measure and record all coil and or unit pressure drops entering and leaving water
temperatures.
13. Measure and record all data from all flow measuring devices.
