Commissioning
The measured handover of a new system: charge verified, airflow set, controls configured, and readings recorded. A commissioning sheet is the reference that later service visits compare against when performance is questioned.
Also called handover, start-up
What is commissioning?
Commissioning is the measured handover of a new system: charge verified, airflow set, controls configured, and every reading written down as the baseline later visits compare against.
Commissioning: how it works
A system that is physically installed is not yet a system that works to specification. Commissioning is where the vacuum is verified, the charge adjusted for the actual pipe run, airflow measured and set, controls configured, and the resulting readings recorded. Without that record, a later visit has nothing to compare against and every question becomes a fresh investigation.
Where you meet the term
- In a handover pack, alongside the manuals and the warranty registration.
- In a performance dispute, where the commissioning readings are what show whether anything has changed.
- In a warranty claim when its terms require evidence of correct commissioning.
How to check it
- Ask for the commissioning sheet at handover. It should carry model numbers, the charge added for the pipe run, airflow or fan settings, control configuration, and the readings taken. Owner check
- Store it with the manuals rather than with the invoice. It is a technical record that a future technician will want, and it is worth photographing so a copy survives. Owner check
- Record readings against the manufacturer targets. A sheet of numbers with no target beside them cannot show whether the system was within specification on the day. Technician
Commissioning: what it is not
- Commissioning is not the same as switching the system on and confirming it produces cold air. It is a set of measurements against published targets.
- A commissioning record kept only by the installer is of limited use. It belongs with the building.
Commissioning questions
What should a commissioning sheet include?
Model and serial numbers for both units, the vacuum achieved, the charge added for the actual pipe run, airflow or fan settings, control configuration, and the operating readings taken with the conditions they were taken at.
Why does it matter years later?
It is the only record of how the system performed when it was known to be correct. Comparing a current reading against it turns a vague complaint that performance has dropped into a measurable difference.
What if I was never given one?
Ask the installer, since many keep records for warranty purposes. Failing that, a technician can establish a baseline at the next service visit, which is worth less than the original but better than nothing.
Where this definition comes from
Written from service manual material held in the HVAC Bench evidence record. Where a document limits a definition to certain models, that limit is repeated here rather than generalised across a brand.
- Multi21+ Service ManualMulti21+ 30K, 36K, and 42K equipment documented in the manual.