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Discussion Starter #1
My home was built in 1975 and has 100A service.

There was some remodeling done in the past in various rooms. New high hats were added, bathroom fans and lights, and ceiling fans as well. There were new breakers added to the box and everything has been running fine. No breakers ever trip with normal day to day use.

I now wish to remodel my kitchen. As of now the refrigerator and dishwasher are on the same 20A line. The hood is on the a line with the counter outlets .

I want to add a compactor and an upgraded hood and recessed lighting. Also, I'd like a separate cooktop and wall oven instead of the 220v range that’s there now.

I know that it's reccommended that the dish washer, refrigerator, hood, and counter outlets have there own line. So at least two more lines would be needed.

QUESTION: How do I determine if I need to upgrade my service? Is there a formula to calculate the max load?
 

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With only a 100 amp service I assume you have gas heat, water heating and maybe cooking also! How many breakers does your panel have, and what is the brand? Are you doing this yourself or looking for a contractor to do this job? It will include replacing the meter base, feeders from the power company into the meter, and the feeders to the panel from the meter. Here is a site with the load calcuations, just fill in the blanks. Any other questions, just ask.
http://www.taunton.com/finehomebuilding/pdf/Service_Feeder_Calculations.pdf
 

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Hey, I have that book where that came from, excellent book on wiring.

I tried to figure out that load calculation myself using that page once, I just about passed out, everything went black and I woke up in a pile of sweat and my own pee.

There has got to be an easier way isn't there? Don't the old timers just look at the old box and base the new one on what they have in the truck at the time?
 

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Discussion Starter #4 (Edited)
jbfan said:
With only a 100 amp service I assume you have gas heat, water heating and maybe cooking also!

How many breakers does your panel have, and what is the brand?

Are you doing this yourself or looking for a contractor to do this job?
- Oil Heat w/ baseboards and the boiler is on its own 15A line.

- 220v Electric cooking & Clothes dryer.

- Label on the box says "Thomas & Betts" and has 24 knockouts

- Currently has:
(8) 15A
(5) 20A
(1) 2 pole 40A -kit range
(1) 2 pole 30A -dryer
(1) 2 pole 20A -20,000 btu thru wall a/c
(1) 2 pole 100A -main
There are three knockouts left unpunched.

- I have dedicated 15A's on the clothes washer, boiler, and one more for 3 exterior motion lights

-I have dedicated 20A's on the swimming pool, and one for fridge/dw

-As far as who's doing the work ...if were talking running 12 guage for the new 20's I'll do it myself, however for service upgrade I'll call you! Wanna come to Long Island? ......I have beer :cheesygri <he said temptingly dangling a bottle from his fingertips>

I did the "Service & Feeder Calculations" worksheet you attached the best I could. I figured for all general lighting and appliances, but I used only the suggested/average nameplate wattage amounts each appliance. When it was all said and done - I came to a calculation that was crazy high.

However, this was the sum of having every single electric using object in my home on simultaneously. If my home is run at 33% of that amount, I believe it would still be high. The sheet said "residential loads are not continuous" and to "consider demand factors".

QUESTION: How much LESS should I consider to determain if I need this upgrade?

Thanks Again
 

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Tell me the square footage of the house and the addition. Tell me the wattages for the cooking units. T&b is not in the panel business anymore, so the breakers may be hard to find. Long Island is a little to far for me to go, and a little too cold also. Making some assumptions I came up that you would need 135 amps. If you can fill out the sheet and email it to me then I can check your numbers. Even if you could get by with the 100 amp panel, you would not have enough slots to make it work. I would not settle for less than a 40 circuit panel and I would upgrade to a 200 amp service. The differance between 150 and 200 should be less than $300 in my book, but that is here in the suuny south!!!
 

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Discussion Starter #6
jbfan said:
--Tell me the square footage of the house and the addition.
About 1800. (I’ve always been unsure b/c I don’t know if it means interior room space or just the exterior footprint.)


jbfan said:
--Tell me the wattages for the cooking units.
Haven’t ordered them yet but strait from an online manual:
Cooktop
Radiant Element(s) 7 in.-1500 Watt
Ultra Power™ Element 10 in.-2400 Watt Dual-Circuit Round
Watt Element(s) 8 in.-1800 Watt Dual-Circuit Oval
Halogen Element 6-1/2 in.-1200 Watt

Wall Oven
Broil Element Rating 1667 Watts
Oven Bake Element Rating 2000 Watts


jbfan said:
--T&b is not in the panel business anymore, so the breakers may be hard to find.
I’ve replaced them already with identical ones from home depot. (I added the a/c line)


jbfan said:
--Even if you could get by with the 100 amp panel, you would not have enough slots to make it work.
I guess I would need to add one for the dw b/c it’s on the same line w/ the fridge, one for a compactor, and one for a canopy hood? Oh yeah a seperate cooktop needs it's own 2 pole as well right? Perhaps I'll do a range.

Do the compactor and hood EACH need a dedicated linel? The manual says yes, but I’m sure they want everything on it’s own circuit.


jbfan said:
--If you can fill out the sheet and email it to me then I can check your numbers.
Thanks I appreciate it. I will if you still would like me to
 

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Come on what is the problem here, just go the code book and it references residential service upgrades. Its not that compliment.
 
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