40 amp
You will need to use #8 wire.
A #14 wire will do fine for grounding a 20 amp device. That is the size of the ground wire in a 2 conductor # 12 wire building cable.
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
Yes, no problem at all going to a larger ampacity of wire. Larger size wire yes, smaller size wire no.
If the wire will fit into the breakers terminal without cutting off any strands from the #8 conductor, then it is OK to use that size. This situation usually happens when a larger size wire has to be used to overcome voltage drop when the load is quite a distance away.
The recommended wire size for a 40 amp breaker is typically 8 AWG (American Wire Gauge).
The recommended wire size for a 40 amp circuit is typically 8 AWG (American Wire Gauge).
The appropriate wire size for a 40 amp breaker is typically 8 AWG (American Wire Gauge).
The recommended wire size for a 35 amp breaker is typically 8 AWG (American Wire Gauge) for copper wire.
The appropriate wire size for a 40 amp circuit is typically 8 AWG (American Wire Gauge) for copper wire.
AWG # 8 copper.
The appropriate wire gauge size for a 40 amp circuit is typically 8 AWG (American Wire Gauge).
AWG # 8
Use 8 gauge wire.
You will need to use #8 wire.
The recommended ground wire size for a 100 amp sub panel installation is typically 8 copper wire.
A 100 amp residential service requires a size #8 copper wire, it should be insulated in green.