The description on the company's website for the item reads as: "for saving and controlling the cost of electricity in hotels, hostels, rural houses, and all types of accommodation. They work by time, by coins or tokens."
The video has since been inundated by people who are shocked that the host would install such a item in their property and expect their guest to pay for it.
"If a host is seriously going to be that stingy, they shouldn’t be renting their house out," said one person.
Another added: "Instant 1 star review."
A third wrote: "Even hotels give you free A/C."
A fourth person shared a similar experience: "We had a Airbnb that had a lock on their thermostat. It was set on 75 - in a Florida summer."
In September, the Spanish government introduced measures to reduce the nation's soaring energy costs.
Indy100 has contacted AirBnb for comment.
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