Not sure if it's associated but main circuit breaker of my house tripped the other night. (I don't know why!) A few hours later after resetting it I noticed a/c not working properly. I know very little about A/C. Could something have simply tripped in unit that I need to reset. It's a Lennox Elite 11 Model # HS29-042-1P (about 11 years old) Thanks in advance for any advice before I call out a a/c/ person.

Did you check the ac breaker to see if it also triped?

The exact thing just happened to me, but it is not a lennox unit. I was wondering myself if this is common.