What causes this?

LAST WEEK I REPLACED A 3 TON AIR CONDITIONER WITH A 3 1/2 ton and today my elec kicked off the whole house except for the ceiling fan and satellite box. Was off for about 40 mins. and came back on by it's self. Called power company no one working on lines. I never had problems before and was wondering if air conditioner could cause this air guy said it could not I am not so sure. Thanks P.S. No breakers tripped

 

The only thing that could cause that is a loss of power from the electric company. Many times they are not aware of a problem when you call, they will however find out later that there was in fact a problem. As for the fan continuing to run...maybe there was an air current that you could not see that kept the fan moving slowly. The cable box, who knows??? Have you looked to see if you have gremlins in the basement or attic?? LOL Sounds like one of those weird moments in time, that you don't tell anyone about for fear they will look at you like you have something growing out of your forehead.

NO THE AIR CONDITIONER COULD NOT CAUSE THIS TO HAPPEN!!

 

The increased load of you new air conditioner of just you working on the lines while installing the a/c unit may have brought to light a loose connection. When you say the a/c went out and other circuits in the house lost power for a while and came back on leads me to believe you have a loose connection in you main service conductors. This loose connection may be in the lugs on your main breaker or fuses, inside the meter base, at the weather head where the Utility company connects to your service entrance conductors, or may even be at the connections of your overhead wires at the Utility company transformer. Check for a loose connection that is showing heating, bubbling of insulation, or melting of electrical tape in all points except inside the meter base and on top of the pole. If you find nothing then ask the power company to open your meter base and check for a loose connection and also ask them to check their connection at their transformer. Leads me to believe you may be experiencing loss of power due to a loose connection in your main feeders.

Let us know what you find

Wg