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I got a new freezer and fridge, each drawing 0.8 amp and 1.2 amps respectively. I'm going to use 14-2 NM-B wire and put them both on a 15amp circuit breaker.

Together they're drawing just 2 amps and sounds like they should be fine, but I wonder about start time current. I could not find anything in their manual, but some googling said the start time current can be up to 10 to 12 percent of working current. So here are my questions: - Is my choice of wire and circuit breaker going to make any issue for my appliances? - If so, should I go for a different type of wire and higher rated circuit breaker or just put them on separate breakers?

UPDATE: Here is an update after almost a year! I used the above-mentioned circuit breaker and wire for my set up and after about a year, there has not been any issue and both appliances are still working fine!

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    Depending upon the type and size of compressor motors, the inrush/startup current may be closer to six or ten times the normal operating current (and even more for some induction motors). However, it only lasts for a few milliseconds -- not enough to pop the circuit breaker. – Upnorth Aug 18 '17 at 20:00
  • Current Code surely requires you provide GFCI protection. I would search for any conceivable way to avoid doing that. Motors are the worst for nuisance GFCI trips, and that will spoil food. Worse, if the GFCI is reset by a passerby and he fails to warn others that the food is spoiled, it can poison your family. "The cook will notice" - not here, our aides don't eat our food, they just shove it on a plate. So for instance find a way to connect the freezer (and only the freezer) to a pre-2011 circuit, and then run a new circuit for the other loads that circuit served. – Harper Aug 18 '17 at 20:25
  • @Upnorth gave a plus but in rush and start current on compressors is usually 1-3 seconds not milliseconds. – Ed Beal Aug 19 '17 at 16:53
  • Okay. Sorry; you're right. I suppose I should have said the MAXIMUM inrush will typically only last for the first AC cycle, i.e., something under 20 mS. How long the entire startup inrush lasts will depend primarily upon the acceleration time, related to the rated torque of the motor (at its rated speed) as compared to the load torque. – Upnorth Aug 20 '17 at 3:59
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You will be fine on the same breaker.

Starting current for refrigerators and freezers is not as bad as you think. Especially, new appliances. They are very efficient and will rarely at exactly the same time.

Good luck!

  • They will when the power comes back on. – Harper Aug 18 '17 at 20:22
  • @Harper good point. Still a 15 amp circuit should be plenty for both. – ArchonOSX Aug 19 '17 at 6:49
  • Yes, one has to consider that ordinary circuit breakers have an inherent "inverse time-current curve"; the larger the overload, the shorter the wait to trip. So, for instance, an 18A load might need to last over a minute and a 75A load only one second in order for a 15A breaker to trip. E.g., interpreting a Square D Type QO, 15A, single-pole curve. similarly, anything more than 105A should trip in under one half-cycle and anything over 70A should not exceed about one second, or it will blow. However, a QO-K may handle 225A for up to 1 second. – Upnorth Aug 20 '17 at 4:33
  • The other thing I just thought of is the defroster on the refrigerator. This is a resistive heater could that draws quite a bit of current but should still be less than 10 amps. – ArchonOSX Aug 20 '17 at 19:10
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The 15A breaker will protect your 14-2 wires, and 15A is plenty to supply your current load.

However, I would recommend you install a 20A circuit and 12-2 wires.

Why? It's a common thing to wire outlets with 12 gauge, and lights with 14 gauge. Also, who knows what will happen 10 years from now? Someone might install more outlets and more loads on that same circuit. Planning ahead will make future upgrade easier.

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