Overcurrent protection hvac mca and mopd

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Well apparently the unit draws 20 amps, the MCA is the current adjustment for a continuous load which makes it 24 amps.
I would not use a breaker smaller than a 25 funny it coincidentally calls out the max size breaker as also being 25. Are you sure the MCA isn't 14amp?
 
codequestion said:
It says the following MCA Air: 15, MCA Elec24, MOPD Elec: 25. What minimum size overcurrent protection beI can use?
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A/C nameplate info has all of the branch circuit sizing and ground fault, short circuit protection calculated by the manufacturer so you want to use what they tell you to use.

No one says you can't use a smaller breaker or fuse but there is no good reason to do so. You'll just end up with nuisance tripping.
 
mopowr steve said:
What is this that lists two different MCA?

I would still say 25 amp minimum.
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If I had to guess, it's that electric heat is optional.

OP, if the circuit is NM, you need #10 with a 25A breaker or fused disco. I see PTAC units all the time that are MCA: 20A, MOPD, 20A (or 15/15). If the nameplate specs are what you write, you need #10 NM (or #12 THHN in a raceway) and a 25A breaker, that is the only legal combo here.
eta: you cannot have 24A MCA on a 20A breaker/fuse. or a 15
 
codequestion said:
I have condensor unit with nameplate MCA: 24A MOPD: 25A. Can I use 15A overcurrent protection circuit breaker?
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Minimum circuit ampacity is just that the minimum. You need 24 amp conductors and a minimum of 24 amp OCPD to meet the minimum required.
 
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