genkuro wrote:
....
Just moved in. The house has a gas dryer hookup. We of course have
an electric dryer.

I did notice a heavy duty socket on the wall. It looks a lot like a
NEMA TT30...
...Any ideas at all on what this
could be? Any chance of hooking a dryer to it?

Maybe; is it in the right location for a dryer or is it in the washer's
spot? If it's in the right spot chances are it was there for a dryer.

Way to tell is, of course, measure the voltage across the two slots to
see. 120V across each to ground/neutral; 240V between the two hots
(assumes USA, of course).

Not too hopeful. But I thought it's worth asking. Short of using
that outlet, what should I expect to pay a contractor to run a proper
250V socket? The garage is finished.
....

Look at the chart here -- surely it will match one of these...

http://www.generatorjoe.net/html/web/outlet/quailplug.html

You could, as mentioned, change out the socket assuming it is wired for
30A/240V, or alternatively, replace the cordset on the dryer w/ one for
the socket (subject to same caveats somebody else noted about breaking
Code going back to the 3-wire connection instead of 4 if that's what
your dryer has)...

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