Air conditioning upgrade and 100 AMP service.

[Terence McCann]

In older homes that have 60 AMP service and have had air conditioning installed I always recommend upgrading the service 100 Amp minimum. Also, all the years that I was in the trade it was always a given however, does anyone have documentation substantiating this?

[Bain]

I doubt you'll find anything in writing. I was always told a 60-amp service could sustain two 240-volt appliances and that a 100-amp service could sustain three. I used to tell people they would have to use a gas range if they wanted A/C and a clothes dryer connected to a 60-amp service.

[Jim Katen]

Originally posted by Terence McCann

In older homes that have 60 AMP service and have had air conditioning installed I always recommend upgrading the service 100 Amp minimum. Also, all the years that I was in the trade it was always a given however, does anyone have documentation substantiating this?

I never thought about it in those terms.

If I have any doubt, I do a quick load calc. It's pretty easy. You'll find a good one in the back of code check electrical.

- Jim Katen, Oregon

[BADAIR]

http://www.codecheck.com/images/CCWet02big.jpg

http://www.codecheck.com/pg00cover.htm

[Terence McCann]

Maybe I'll check with a few of the local municipalities. Perhaps when pulling permits they wanted to see the service upgraded to 100 AMP. Wish I could remember where I heard that.

Out of all the things I lost I miss my mind the most.

[Terence McCann]

Getting back to this for one more question.

How many do a load calc when needed?