Answered after this number called several times over a period of a few days. Caller said he was calling from Home Energy & needed to make a safety appointment to inspect the furnace. He knew my name & address so I stupidly made an appointment & gave him my email address so he could send a confirmation. Have not received the email & now, after looking up the number, I realize it's probably a scam. Will be interesting to see if anyone shows up for the "appointment"...