CIBSE's Commissioning Code A describes air-system setting to work, testing and regulation. The engineer needs a requirement to compare with measured results. Where drawings or targets are missing, arrange assessment rather than assuming the present settings are right.
Check readiness before adjustment
The system must be ready for reliable measurements. Check its operating mode, controls and components first. Blocked filters, damaged ducts or faulty equipment need attention rather than attempts to compensate elsewhere.
Arrange access to the unit and test points. Agree how the building will operate while readings are taken, and have those conditions recorded. Changing demand or fan speeds can make comparisons unreliable.
Understand what balancing can and cannot resolve
Balancing addresses distribution that differs from the design. It cannot create capacity that the equipment or ducts do not have, or fix a broken component. A room that feels wrong may also have control or heat-gain problems.
Have the causes distinguished before changing flows. Increasing supply to your room may affect another branch, so the engineer needs to consider the wider connected system.
Use the results after the visit
Ask for the system details, intended flows, measured results, final settings and anything still outside the requirement. Room and terminal references should show exactly where readings were taken.
If the target is not achieved, request the reason and next action. Repairs, more design work or a separate instruction may be needed. Save the results with service and commissioning records for future changes.
Review after system changes
Recheck relevant measurements when equipment, ducts or controls change the distribution. Identify which parts are affected so the work has a defined purpose rather than automatically repeating everything or relying on old settings.
FAQs
Does balancing mean cleaning the ducts?
No. Cleaning deals with contamination; balancing measures and changes distribution. Your system may need both jobs, but one does not complete the other.
Can balancing fix every uncomfortable room?
It cannot. Check that airflow distribution is the cause; equipment capacity, controls, room use and other conditions may explain the problem.
What should we provide before the work?
Send the layout, target flows, commissioning records, operating details and rooms affected. Explain recent changes and which information you cannot find.
Related help
See Air and Ventilation Balancing, Ventilation and Air-Handling Units, or read what an air-handling unit does. To discuss system performance, describe the affected rooms and the result you need.
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