Air conditioning failures on Italian trains have become a recurring problem during summer heatwaves, with passengers reporting sweltering carriages, older trains with no working air conditioning at all, and breakdowns that leave people stranded in the heat for hours.

When the air conditioning fails completely, Trenitalia offers passengers a partial refund – though passengers need to check the terms and conditions carefully.

The problems have hit different train types and routes across the country this summer. On June 19th, a Trenitalia Frecciarossa train from Milan to Bari set off with some carriages already lacking air conditioning, then broke down and stopped for three hours, with temperatures inside reaching 40C.

“People were passing out all the time,” one passenger told Fanpage. “They didn’t even give us water: the water finished in the first few carriages, and that was it.”

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In July, a Frecciarossa set off from Reggio Calabria to Turin with four carriages without functioning air conditioning, forcing passengers to endure stifling heat during the 12-hour trip, according to La Stampa.

Passengers complained until staff evacuated the first carriage, leaving people standing in corridors and looking for space elsewhere. The failure affected at least 400 passengers who boarded along the route.

"My children risked falling sick," Agnese Alessi, a mother of twins travelling with her children, told La Stampa. Alessi said she tried to cool the children with cold water and iced tea from the train's bar, but the heat became unbearable and she had to ask to move to another carriage.

Passengers on regional trains on the Bolzano-Bologna line flagged a lack of air conditioning at the end of July, when outside temperatures topped 38C.

In these temperatures, “air conditioning is not a luxury but an essential requirement to guarantee a safe and dignified trip,” said Paul Köllensperger, a Bolzano councillor, who requested more information about the causes of the failures and Trenitalia’s obligations to its customers.

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Trenitalia has a policy of offering a partial refund of 25 percent of the ticket price in cases of complete air conditioning failure on its trains, unless passengers refuse to move to another seat where air conditioning is working.

The refund applies on Frecciarossa, Frecciargento, Frecciabianca, Intercity, Intercity Notte and Freccialink services, but not on regional services like that on the Bolzano-Bologna line.

Passengers can request the refund within 12 months from their trip and ask for a voucher or a new ticket of equal value.

However, the refund is not available in every situation. For instance, people travelling with season passes might not be eligible, and if the train is delayed, passengers might only be able to request a refund for the delay.

Trenitalia also states that passengers have to report the fault to the train manager (capotreno) during the journey, so that it is logged in the onboard register. Without that record, the claim can’t be processed.

Passengers can check the full terms on Trenitalia's website before making a claim.