Electrical Wiring in the Home/added electrical load


We recently bought a house built in 1962. It has an ITE 125 amp load center with 6 double breakers which include house power (to inside breaker panel), Range, Water Heater, Dryer. I am adding 2.5 ton central Air Conditioning that requires two circuits to air handler with electric heat strips (one 50 amp and one 25 amp) and one circuit to condenser that is 25 amps. I also want to add 30 amp RV outlet and a circuit to a new heater/ventilator/light in one bathroom.
In order to accommodate added loads, my choices are to either replace the 125 amp load center with a new 200 amp load center or to add another 125 amp in series to the existing load center. This second option is the most economical and easiest to install. I would feed the second load center from a new 100 amp breaker in the old load center.
My question is: am I in danger of overloading the old load center by adding the second one? It was suggested that I connect the wire to the new load center in the old one ahead of the bus. This will not give the disconnect that I think may be required by code.
Your advise on this issue would be greatly appreciated.
Tommy Stellman

Hello Tommy,
My name is Robert and ill be helping you today and in response to your question you CAN NOT ad a 200a panel w/o first changing the incoming service feeders to 1/0 wire which can be costly and requires changing the service pipe outside your home to 2" along with a different meter pan, weather head, panel, etc... so i recommend simply adding a 100a sub panel using #2 wire and adding a 12/24 circuit panel and you will be just fine.Should you need any other help be sure to ask and please take a minute and fill out the survey it helps us .thank you
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Electrical Wiring in the Home

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Robert Tomasulo


I am here to answer ALL your questions regarding anything to do with home wiring such as Switches, Receptacles,Lighting, Main Distribution Panels, HVAC, Thermostats, etc; if it has a wire and in your home I CAN ANSWER IT. Whether its as simple as "why do my lights flicker?" Or as complex as I would like to rewire my house im here to help, in addition i can offer advice on remodeling a kitchen or lighting up you back yard as well as offering troubleshooting on appliances.


I have over 17 years in the electrical industry including Residential, Commercial & Industrial, Im also a certified HVAC technician as well as a certified fiber obtic technician.I am currently employed by the New York City Transit Authority as the Senior Electrical Maintainer and serve as the Relief Foreman for the electrical maintenance division for the past 12 years.I also hold many certifications, licenses and certificates in my field

FOA Member(Fiber Optic Association) UTU (United Transportation Union) IBEW (International Brotherhood of Electrical Workers) HVAC/TALK (Heating & Air conditioning troubleshooting group)

5 years of technical school after high school in electrical installation and design sponsored by Local 3 (IBEW) As well as over 17 years of hands on in the field training and education, and till this day im still learning, Not a day goes by that i don't learn something and if i feel i didn't i will open up a book to insure I DO!

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