Eval- arrived to customer stating there was a loud noise going off in the hallway where the thermostat and the unit are Upon a thorough evaluation, I was able to determine that the smoke alarm is going bad Recommended an Electrician to come and a Duct cleaning, home is over 25 years and ductwork has never been cleaned since being built and customer has 7 pets in home despite changing filters weekly, small particles are still able to make their way through Duct cleaning is on their plans for spring time Electrician is scheduled to come out tomorrow to replace smoke alarm that has been there since being built