Should a data centre have a thermographic survey before the defects liability period ends?

Yes, if you want the evidence while the installer is still responsible for defects. A survey under real IT load in the last months of the defects period can show connections that commissioning at test load could not, and gives you measured, located findings to notify before the period closes, while access and responsibility are still clear.

Why commissioning isn’t the last word

Commissioning thermography images new equipment under load bank or test load, usually over a few hours. That is the right moment to find installation problems, and it gives the site its first baseline. But it is a snapshot. In the months after handover, halls fill with real customer load, fit-out adds tap-offs, breakers and cabling to equipment already in service, and the load settles across phases and A and B supplies in ways a load bank does not reproduce. A connection only shows heat when current flows through it, so equipment that looked clean at commissioning may not stay that way once it carries real load.

What the defects period means for thermography

Most build contracts give the installer a period after practical completion during which notified defects are theirs to put right. A finding raised inside that period is a defect notice with evidence attached. The same finding raised a month after it closes may become a maintenance job for the operator. Check your own contract for what counts as a defect and how it has to be notified, then plan the survey around that date rather than the annual PPM cycle.

When to time the survey

Leave enough time. Allow for the survey, the report, notifying the installer, the repair and a follow-up image, all before the end date.
Wait for representative load. Survey once customers are live and running normally, not during migration or a quiet week.
Record the load. Every image should carry the load at the time it was taken, so it can be compared with commissioning and with later surveys.

What to include

Cover the supply path, not just the new halls: main LV switchgear, busbar trunking and tap-off units, UPS input and output, PDUs and rack PDUs, generator and ATS changeover panels, and the electrical supplies to cooling plant. All of it can be imaged live, with nothing switched off. Covers are opened by the site’s authorised person under its own permit system.

What the report should give you

Each finding should state the measured temperature, exactly where it was taken, the load at the time and the difference in °C from a matching reference, with a thermal and visual image pair. That is what turns a finding into a defect the installer can locate and act on. It also gives you a direct comparison with the commissioning record.

A good commissioning record makes this easier. On a London data centre build, our commissioning thermography found 16 busbar sections over 80 °C under test load, the highest 103.5 °C at a tap-off unit, all located and recorded before handover. A survey before the defects period ends checks the same equipment again, this time under the load it was built to carry.

What Ti does and doesn’t do

Ti Thermal Imaging inspects and reports. Our ITC Level 3 thermographers image the equipment live and reports are produced on site. The installer or the site’s electrical contractor investigates and carries out any work.

Frequently asked questions

Does this replace commissioning thermography?

No. Commissioning thermography finds installation problems under test load before handover. The end-of-defects survey checks the same system after months of real running, while the installer is still responsible.

Who should commission the survey?

Usually the operator or the client’s team, so the findings are reported to the people who will own the system once the defects period closes.

Can it be done without downtime?

Yes. The survey is non-contact and carried out with everything in service, working within the site’s change and permit process.