15amp breaker on air handler with 2.3 overcurrent amps
My new split system air conditioner (not a heat pump) has a 40amp breaker in the main box (Note: these are all standard breakers, not the new ones). A 10 gauge wire runs to a subpanel with a 25amp breaker for the outside condenser unit and a 15amp breaker for the air handler (in the attic). The outside condenser unit has a rating of 25 overcurrent amps. But the air handler has a rating of 2.3 overcurrent amps (from the chart in the manual). So I'm thinking this 15amp breaker is overkill. But the 25 and 15 switches add up to the 40amp on the main panel (does that mean they couldn't put anything less?).
But since I've got a 10 gauge wire running between the subpanel and the main panel breaker, the main panel should have a 30amp instead of a 40amp breaker (I think). But since the total overcurrent amps on the condenser and air handler add up to 27.3 then that's less than 30 so the 10 gauge wire should be safe. So are the 25 and 15 breakers in the subpanel going to protect me from worrying about too much current flowing on that 10 gauge wire back to the main panel 40amp breaker (which is apparently too large otherwise) if they malfunction?
Also, should I worry about that 40amp main panel breaker allowing too much current to pass through from main to subpanel if the only two machines on the subpanel should never draw more than 27.3 overcurrent amps?
Thanks for reading,
Morty
To help you visualize:
Machine______________________________|subpanel| 10 gauge wire |mainpanel
A/C condenser (25 overcurrent amps) >>>>>> 25amp \ _____________ 40amp
Air handler (2.3 overcurrent amps) >>>>>>>> 15amp /