For a 50 amp breaker, you would typically need a 6-gauge wire.
For a 30 amp breaker, you will need a wire that is at least 10 gauge in size.
6
For a 50 amp breaker, you will need a wire that is at least 6 gauge in size to safely handle the electrical load.
AWG # 10 wire.
Look on the heater and see what amps it is pulling. That will determine the wire size and breaker size. It must be on a dedicated circuit. 15 amps = AWG # 14 wire with 15 amp breaker 20 amps = AWG # 12 wire with 20 amp breaker 30 amps = AWG # 10 wire with 30 amp breaker 40 amps = AWG # 8 wire with 40 amp breaker
You will need to use #8 wire.
8 AWG is typical.
The recommended wire size for a 50 amp breaker is typically 6-gauge wire.
When installing a circuit breaker, you size the breaker based on the wire size. The breaker should be matched to the ampacity of the wire to ensure proper protection against overloads and short circuits. The device being controlled by the breaker is not a determining factor in sizing the breaker.
It is not the number of bulbs that you worry about. It is the wire size that is your concern. If the circuit is wired with AWG 12/2 wire then use a 20 amp breaker. If it is wired with a AWG 14/2 wire then use a 15 amp breaker. You are protecting the wiring with the correct size breaker.
The recommended wire size for a 20 amp breaker is typically 12-gauge wire.