wrote in message
oups.com...
We've only been in our house (30 year old home) for a few months. We
can tell whenever the AC or furnace kicks on because there's an almost
imperceptible dimming of the lights. Can someone explain the possible
reason(s) for this? We have a home warranty and if this is something
serious then we'd like to have it addressed quickly.

Thanks!


A few suggestions here.

1 Now being able to see the amount of dimming there is no way of telling
if you have a problem over the net
2. There are three things that can cause this that I know about, maybe
four
3 You have to think of the wire in your home as water pipes to help
understand what I'm going to tell you

A If there is something wrong with the AC this could cause this problem,
to much power required to start a tight compressor
B If there is a loose wire this could cause this problem, causing high
amp draw, think of a valve downstream of the main.
C A bad electrical panel
D Corroded wires at the pole or mast.

I have seen two jobs that were serious in nature and a dozen that weren't.
Older homes had smaller electrical entrances and that is like smaller water
pipes, your only going to get so much water through a small pipe. The same
is with wire, only so much power and if you have a lot going on and the AC
starts your lights will dim for a second. This is normal but not desired,
but not necessarily dangerous by any means.

I have seen a homes lights dim when a belt drive 1/4 hp motor started on the
furnace, ALL the lights dimmed. I knew then that the wire (think of a pipe)
somewhere at the box supply entrance to the utility pole outside had to have
problems. Told them I would not put a furnace or AC in until its repaired.
They called an electrician out and he said I was crazy. Called another and
they didn't think there was any problem. I still refused and the homeowner
called the utility guy out. Here the wires connect at the mast, (wires
outside the house connected to utility wires) were completely corroded and
ready to fail! The utility company replaced the wires from the street to
the home and solved the problem. This could have caused the home to burn
down

The other major problem was corrosion INSIDE the main electrical panel
itself. Once again and electrician didn't think there was any problems. I
used my inferred thermometer and found one circuit dangerously hot!! The
buss inside the panel was corroded on one breaker. Changed the breaker box
out and problem was solved.

So, you may not have a problem and yet again this may be an indication of
major problems in the future.

Hope this helps
Rich