For a subtropical city in the developed world, Brisbane had for a long time an oddly ambivalent attitude towards air-conditioning. Outside of office towers, shopping centres and movie theatres, you were generally left to get sweaty.

But not on Queensland Rail’s EMUs. The venerable electric trains have always been the Snowpiercers of Brisbane’s transport network: insanely noisy, and with air-operated doors that occasionally don’t work, but at least you’re trapped until the next stop in icy, air-conditioned comfort.

Not so Queensland Rail’s New Generation Rollingstock (NGR) trains. The Brisbane Times reports commuters are complaining about the air-conditioning on the new carriages, which finally began to take passengers last month.

Commuters have been leaving negative posts on advocacy group Rail Back on Track’s Facebook page.

“We have been getting some feedback and complaints for quite a while,” Rail Back on Track administrator Robert Dow is quoted in the Times as saying. “People are saying that it is hot and humid inside the new trains. It has come up enough times now and for long enough for us to think this could be a bad problem.

“We think the temperature needs to be turned down a few degrees.”

The negative Facebook comments have prompted a response from TransLink, which confirmed to RBOT that it is trialling ways to improve the air-conditioning.

Queensland Rail plans to have between 10 and 15 NGR trains running in south-east Queensland by the time the Gold Coast Commonwealth Games kicks off in April.

Overall, 75 new trains have been ordered, but they have been plagued by issues since the first units arrived from India in 2015, including problems with brakes, ventilation and driver visibility.

The new trains’ air-conditioning has been put to the test during the sweltering weather of recent days, which saw the mercury climb to 38 degrees on Sunday, the city’s highest January temperature in 18 years.