Unknown, it came from one of the field contractors. The electrician probably put in a 15 amp breaker, but the HVAC contractor was questioning the wording as well. Very confusing
What wording? “For HVAC Use”?
Edit
It’s not about the size of the breaker, it’s about the type of breaker/fuse.
This may help:
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Sounds like a misprint on the nameplate. If you follow it you can use #14 AWG conductors and either 15 amp circuit breaker or a 25 amp fuse (standard size). All modern circuit breakers are HACR type.
This subject was a PIA back in 2006, and still is. IMHO it is way beyond what HI’s are required to inspect (rather analyze).
A fuse and a breaker are not the same thing. Thus, different ratings.
An HVAC fuse and breaker are not the same as non-HVAC protection devices.
An HVAC Breaker or fuse is designed to take the momentary “startup” load that regular, less costly breakers are subject to. HVAC rating is a device that allows “over current” but not a direct short. Normal fuses open from over current, just like a direct short.
Do you know by looking at the breaker/fuse as to what it is rated for?
There are breakers in the panel on the side of the house and fuses inside the equipment panel sometimes. Which one is which, and which one does what? Depends…
If you do not see a grossly oversized overcurrent protection device, or grossly undersized wire (based on its type and rating), is this something you want to get into?
If we look at the nameplate, Compressor 7 RLA, 12 LRA. What does this mean?
7 amps is what the compressor runs at under a designed load.
12 amps is what the compressor draws if the crankshaft is locked. This is close to what it draws when it starts from a stop (dependent on residual refrigerant pressures).
So which fuse do we need, 15 or 20?
Put in a 15 from the local gas station, and it will blow on start up.
Buy one from HVAC Parts Store rated for HVAC, it will not blow.
It costs more, so which does the homeowner elect to buy and install themselves? 
“Approved for” on the data plate, means the equipment can handle the extra surge at startup.
Its all about how fast they want the fuse to blow to protect their equipment.
Just report what you can take a picture of.
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All circuit breakers have been HACR rated since the 90’s when UL changed the standard for testing so unless your equipment is very old a modern inverse time circuit breaker will work just fine on any AC equipment.
From Square D:
History of HACR Ratings:
For many years Underwriters Laboratories® (UL)® required special testing of circuit breakers used in group motor applications in air conditioning and refrigeration equipment. UL had Listed these circuit breakers as HACR Type and they were used to meet the requirements of Article 430.53(c)(3). At first, UL restricted the HACR listing to circuit breakers rated 240 Vac or less and 60 A maximum. In the early 1990s UL redefined the test parameters for UL Liste HACR Type circuit breakers, resulting in HACR ratings for circuit breakers rated 600 Vac and less and 250 A maximum as a second step. By these test parameters HACR Type circuit breakers were the same as other types of inverse-time circuit breakers except they were additionally investigated by UL and determined to be suitable for motor branch circuit protection on group installations. Initially, these circuit breakers were tested and Listed to UL 489 the standard for safety for molded-case circuit breakers. Then additional investigation was done including tests to determine that the circuit breaker provided appropriate protection for the circuit components of typical heating, air conditioning, and refrigeration equipment. These included compressor motors and fan motors connected in group motor applications.
HACR Ratings Today:
A great number of circuit breakers were investigated by UL using the special HACR testing. It was found that all circuit breakers that passed the normal UL 489 tests also passed the special HACR testing without a special design. As a result, UL 489 has been revised to recognize that all circuit breakers that satisfy the construction and test requirements for UL 489 Listing are also suitable for
HACR applications:
Section 7.8 of the 11th edition of UL 489 grants HACR listing to all UL 489 Listed circuit breakers. There is no longer a requirement for special testing. These circuit breakers are suitable for group motor applications requiring HACR designation.
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Another good reason for a HI not to be playing electrician…
However, this is about new breakers (new construction). There are still old one’s in use (not requiring replacement because they are not new) and some that may have been replaced with old non-HVAC rating.
It is nice to know this stuff should you get a call or come across a unit tripping the breaker or blowing fuses. It may not be a problem with the equipment…
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