Another movie similar to this?

I remember this movie well from when I was a kid, but there was another one that involved an entity or something like that in electricity. I remember a scene where a woman takes a shower and the thermostat or something turns up on the water heater and she ends up getting severely scalded. There was another scene at the end where the main character chops down a telephone poll with a chainsaw (it could have been an axe, I can't quite remember). There was also a scene with a TV that goes crazy, and it shows a shot of the circuit board melting down.

Anyone else remember the movie I'm talking about?