A two-alarm fire that heavily damaged the basement of a two-family home on Orchard Street was caused by a condensation pump on a furnace, said Watertown Deputy Fire Chief Tom McManus.
, started when a the condensation pump short circuited and lit flammable items in the basement.
"There was possibly a short circuit with the condensation pump to the furnace," McManus said. "Some debris near it may have ignited." McManus said.
Most of the fire was contained to the basement, but flames did damage the first floor of the house at 81 Orchard St. The rest of the house suffered smoke and water damage.
None of the residents were hurt in the fire, but a pet cat died from smoke inhalation. Other pets in the house, including another cat and a chinchilla, were saved.