Commissioning in August: why we test at 50°C on purpose
Any cooling system works in January. We schedule the hard tests for the exact weeks the climate is trying to kill the design, because that's the performance the client actually bought.
Marwa El-Sayed
Commissioning Manager, Green Square
There is a version of commissioning that exists to produce paperwork: run the plant on a mild spring morning, record the numbers, sign the forms. The building 'passes'. Then August arrives, the condensers meet 50°C air for the first time in their lives, and the phone starts ringing.
We schedule against the weather instead. Heat-load rigs stand in for a full house of guests, gas coolers and condensers are proven on the worst afternoons the season will give us, and systems are deliberately failed (a chiller tripped at peak, a pump isolated mid-cycle) while the loggers watch the recovery.
What summer testing catches that spring testing cannot
- Condensing plant that derates faster than its datasheet admits
- Controls hunting when every zone calls for cooling at once
- Thermal expansion no one calculated, pipework, joints, structure
- Standby plant that starts, but cannot carry the real peak
On our Lusail tower we resistive-loaded entire guest floors through the hottest fortnight of the year and balanced the systems against design conditions, not calendar convenience. The operator moved in knowing the building had already survived its worst week, because we had the trend logs to prove it.
“January commissioning tests the paperwork. August commissioning tests the building.”
It costs more to commission this way. It costs far less than discovering the truth with guests in the rooms.
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