The breakers are intended to protect the wiring, not the devices. If you can determine the wire size behind the panel it will determine what amperage you should have for the breaker.
That being said - from the information located from the link below (2005 - but should be similar) it looks like it’s likely either a 10guage wire (main salon) or a 14guage wire - other tv/stereo? 14guage wire would normally use a 15amp breaker while the 10guage would be 30amp. (From the Blue seas wire ampacity chart below)
Using a smaller breaker is fine as long as it has enough capacity for your equipment, do not use one larger than what the wire is rated for.
Not sure on that model boat, but for my 2009 Hunter 41DS, both the AC and DC panels and associated equipment, including replacement breakers, were sourced from Paneltronics (
Paneltronics: Electrical Panel Manufacturer).
I was surprised that the 'entertainment' had a 40-amp breaker. My boat had the Bose entertainment system and a dedicated inverter for it. As-built on the DC panel that I was able to identify was:
Left:
30amp; 10ga; cabin lights
10amp; 14ga; courtesy lights
40amp; 10ga; entertainment (label is 34/40 which maps to 40)
20amp; 10ga; macerator
15amp; 12ga; water pump
25amp; 10ga; sump pump
40amp; 10ga; head (label is 34/40 which maps to 40)
? ; 16ga; windlass - 5 amps
15amp; 10ga; refrigerator
15amp; 10ga; freezer
10amp; 12ga; blower
Right:
? ; 16ga; anchor light - 5 amps?
? ; 16ga; Steaming light - 5 amps?
10amp; 16ga; deck lights
10amp; 14ga; running lights
10amp; vhf ; vhf
? ; BIG ; Autopilot - 40 amps?
? ; 14ga; Raymarine C120 10/15?
