Fire crews from Spreydon, Harewood and Wigram attended the call out at the university's Nancy Simms block just before 7.45am.
Fire and Emergency spokesman Ian Littlejohn said it is normal protocol to send three crews to a sprinkler detector.
"We treat every call like this as a fire," he said.
Two crews also attended a hedge fire in Southbridge on Tuesday morning, which took more than an hour to put out.
Meanwhile on Monday about 11.30pm, crews responded to a fire in a toilet block at a Kaiapoi park, which was deemed to be suspicious.
Firefighters found paper had been set on fire in the toilets at the Charles St park. Police were called and spoke to witnesses at the scene.
