If you don’t have a working carbon monoxide detector in your house, get one. Matt Davis’ parents, John and Peggy Davis, died last month of carbon monoxide poisoning, apparently due to an exhaust leak in their oil furnace. The couple went to sleep and never woke up, Matt said. They lived in Worthington, Ind. The couple did not have a working carbon monoxide detector. Carbon monoxide detectors are available at Lutak Lumber, Haines Home…