What some of the others said:
220/240 V is a tad more efficient, as the lower current has less "IR" drop
in the feed wires associated with it.
And, in addition to being easier on the wires, 220/240 inherently balances
the load lines coming into the house.
It is possible, with numerous large 120 V devices, to load only one leg
coming into the house, unless you explicitly balance stuff.
I deal with this all the time. :(
With 220/240, you don't have to worry about it.
Always go 220/240 when possible. Whenever possible, I rewire motors from
110 to 220.
In some cases, 220 just isn't readily available in some parts of a house.
Then, yer stuck w/ 110/120
Mr. P.V.\'d (formerly Droll Troll), Yonkers, NY
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