What is the Minimum breaker size required by NEC for #14 Copper wire feeding a A/C minimum 18.5 amp and 25 amp Max over current protection?

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What size wire, of the type (NM, MC, THWN, etc.) you intend to use is rated at 18.5a or better?

We usually don't like to just answer such questions, preferring to teach you how to figure it out.

Added: Is that 18.5a the MCA or minimum breaker?
 
Do you mean a MCA of 18.5 and a max OCPD of 25 as stated on the label? If so the conductors could be #14 using 75 degree conductors (pipe and wire) of if using NM cable they would need to be #12 as NM must use the 60 degree ampacity.
 
NM cable is limited to the 60° C ampacity which is 15 amps for #14 AWG. Use MC cable or pipe and wire and you can use the 75° C ampacity.
 
Roger Stevenson said:
Doesn’t #14 Copper have an asterisk and footnote requiring 15 amp breaker maximum and #12 20 amp breaker Maximum and #10 30 amp max?
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The * in the ampacity table sends you to 240.4(D), the small conductor rule. The parent text says the rules in 240.4(E) or (G) can override the small conductor rule. The rule in 240.4(G) says that the conductor sizing and overcurrent protection rules in Article 440 apply to air conditioning circuits.
 
Roger Stevenson said:
Yes 14-2 romex
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don_resqcapt19 said:
The * in the ampacity table sends you to 240.4(D), the small conductor rule. The parent text says the rules in 240.4(E) or (G) can override the small conductor rule. The rule in 240.4(G) says that the conductor sizing and overcurrent protection rules in Article 440 apply to air conditioning circuits.
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So 14-2 Romex is allowed on a 20 amp breaker?
 
Yes, if it feeds a motor, HVAC unit, or some of the other exceptions. The MCA would need to be 15A or less though.
 
The title and the first post are different questions.
Roger Stevenson said:
What is the minimum wire size required by NEC for a A/C mini split system with a minimum 18.5 amp and Maximum 25 amp over current protection?
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If this is the question then I would say 14 gauge wire is fine with a 25 amp overcurrent protective device. That is assuming it is not nm cable. Since the info isn't given then I would use t. 310.16
 
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