Using the AC to beat the rising temperatures in Keralam turned dangerous for an elderly couple here who narrowly escaped with their lives on the previous night as a short circuit in the machine resulted in a fire that completely gutted their bedroom, fire force officials said on Saturday. The couple had just turned in for the night at around 9 pm when there was a short circuit in the AC, and it caught fire, an official from the Pathanamthitta fire station said.