While we were cleaning out a friend's garage I turned on a heater fan. I didn't take a good look at it but it has a digital display, thermostat, and I'm pretty sure it's a wire element type. It started getting dark while we were cleaning and my friend was moving something around and told me to turn off the heater so that the light would get brighter. I turned it off and the fluorescent light in the ceiling got way brighter and stopped flickering.
I haven't had a chance to look at the breaker box yet, but from what she describes to me, it sounds pretty bad. She says that if you turn too much stuff on in the house, the breaker trips. I'm assuming that the whole house is only on a few circuit breakers.
My question is, why would the heater fan cause the fluorescent light to flicker and dim, and can I expect this same behavior from incandescent or LED bulbs (non-dimmable)? Is this indicative of improper wiring in the house, or just too much going through a single breaker, or is it maybe something with the (probably) shaded-pole fan inside the heater causing noise in the grid?