Max Fuse

[ROBERT W. NEWLAND, JR.]

Data plate on A/C unit call for a max fuse of 25 Amps. Main Panel has (2) 20 Amp breakers together. Is this OK? (3rd and 4th breakers on right side in off position)

[Marc D. Shunk]

Yes, 20 is less than 25, so you're okay if it permits breakers.

[Michael Larson]

Check mfg. site for AC model number.
Many have both a max. fuse size and max. Circuit Breaker rating.

[ROBERT W. NEWLAND, JR.]

We're good. Thanks!

[Greg Fretwell]

The only down side of that might be a nuisance trip. Maybe a PITA but not a safety issue

[Paul W. Abernathy]

Is this new construction......if so have them re-identify the white conductor going to the breaker.

And just remember..( and I think Marc touched on it )...if by chance you are ever dealing with an older AC unit outside and it says Maximum Fuse Size and says nothing about breakers...it MUST have a fused OCPD somewhere in the setup.

[Richard W. Washington]

Originally Posted by pabernathy

Is this new construction......if so have them re-identify the white conductor going to the breaker.

And just remember..( and I think Marc touched on it )...if by chance you are ever dealing with an older AC unit outside and it says Maximum Fuse Size and says nothing about breakers...it MUST have a fused OCPD somewhere in the setup.

fused OCPD?

[Marc D. Shunk]

Originally Posted by rwashington

fused OCPD?

Fused overcurrent protective device. In a home with breakers, this would normally be accomplished by providing a weatherproof fused disconnect at the unit where a normal weatherproof unfused safety switch would normally be found.

[Greg Fretwell]

The only reason they would say "fuse" is if the number they came up with was a non-standard breaker size. You can get fuses just about any size. Most inspectors would take the next smaller breaker. (a few overly generous ones might even let you round up)

[ROBERT W. NEWLAND, JR.]

Ooops, My bad. I meant Max BREAKER in my original post. I'm feeling "old school"

[Paul W. Abernathy]

lol...well robert if you mean 25A Max Breaker.....just make sure it is not protected by a breaker larger than 25A.....

Just remember most nameplates will say Minimum Circuit Ampacity and Maximum ( in your case breaker ) OCPD size......this is where you see many times smaller sized conductors on larger breakers...make it simply for yourself...just verify the items on the nameplate and let er ride....