To protect devices and equipment from overcurrent.
A breaker switch is easier to use.
Use a 30 amp breaker.
Depends on the wire size used in the circuit. If you use AWG # 14 wire you must use a 15 amp breaker. If it is wired with AWG # 12 wire then you use a 20 amp breaker. If a AWG # 10 wire is used then a 30 amp breaker is required. The breaker protects the wiring from overheating so you must use the proper size breaker for the wire used.
The size breaker you use is determined by the size wire used in the circuit. If you use AWG #12/2 wire then use a 20 amp breaker. If you use AWG # 14/2 then use a 15 amp breaker.
The recommended type of breaker to use for a hot tub that requires a 50 amp GFCI breaker for safety is a 50 amp GFCI breaker.
The breaker you use is determined by the size of the wire in the wall not by what is being connected to that circuit. If you have 14/2 wire then use a 15 amp breaker. If you have 12/2 wire then use a 20 amp breaker. The breaker protects the wiring not the item connected.
25 amp breaker
You will need a multimeter to check a 220 volt breaker. You should unplug appliances that go to that particular breaker. Use the multimeter at the breaker to check the voltage. If it shows 220, then the breaker is okay. If it doesn't, then the breaker is no good.
For typical residential house wiring 12 AWG wire is required for a 20 Amp breaker. If you change out the breaker for a 25 A breaker you would have to rewire the circuit with 10 AWG. In that case you could up the breaker to 30 Amps. All outlets and switches should be rated at the same voltage and current as the breaker.
15 amp breaker.
The recommended amperage for a breaker to use with a 30 amp dryer is 30 amps.
The recommended amperage for a breaker to use with a range is typically 50 amps.