"leza wang" wrote in message
...
my home is like 70 or even more years old (not sure really). I want to
know if i should upgrad the wiring. the electrical panel shows i have
100 amp. I have been told if i have knob 2 wiring then i should change
it to 3 knob wiring. My question, how can I know if i have 2 knob
wireing or 3? in the main floor, i have all power outlet with 2 holes
(+,-) upstair I have power oullet with 3 holes (+,-, ground)
Thanks a lot.

Knob and Tube wiring. Time to upgrade, especially if you are putting loads
like air conditioners. Call a competent electrician or two for estimates
and recommendations.