Electrical Wiring in the Home/Maximum load for 15 amp circuit


We have a small sunroom that we added several years ago.  Because it was added, we decided to use auxiliary heating and A/C (i.e. a 60 inch baseboard heater and a "portable" floor A/C unit.)  The original A/C unit (7500 BTUs, 6.8 amps) died last week.  I'm replacing it with a 10,000 BTU unit (9.2 amps).  When we built the sunroom,  the builder put in a separate circuit @ 15 amps total.  We have never had a problem with tripping the circuit, but the new A/C (being larger) will draw more amps than the old one. And, there is a very small refrigerator on the same circuit, 1.3 amps. (Of course, the baseboard heat and A/C will never be on at the same time.)

So --  in the warm months, here's what will be running in the sunroom:

A/C -  9.2 amps

Small refrigerator = 1.3 amps

Small ceiling fan:  ?? - maybe 2 amps?  (doesn't run all the time)

So this adds up to 12.5 amps.  Is 15 amps sufficient?

Most Air conditioners say to use their own circuit. When the compressor first comes on, it will use more power momentarily. However, with your math, it looks like everything will work. However, you don't mention any lights or TV or anything else. If you can run another circuit, it would be the best. If not, give it a try, and make sure the breaker does not trip, and nothing is warm to the touch.
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Electrical Wiring in the Home

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Bob Sponaugle


Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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