Wiring question

[vnmyers13]

So after going back and forth multiple times have decided to go to a 2 element single pid system.

Using the drawing the the one and only PJ of course came up with I am trying to verify which segments of wire need to be 10 gauge vs which can be 12 or 14 gauge?

 

[thargrav]

All depends on amperage.

For up to 30 Amps you need 10 Gauge.
For up to 20 Amps you need 12 Gauge.
For up to 15 Amps you need 14 Gauge.
Control circuits can be much smaller, like 22 Gauge, because they draw very little current.

In your case everything directly in-line between the elements and power source needs to be 10 Gauge because the elements will draw more than 20 Amps. But everything else can be much smaller, like the 22 Gauge I mentioned.

 

[vnmyers13]

Perfect thank you. That is what I thought. And it is 30 amp service. I have a lot of 14 gauge so the rest will be wired with that.

The 10 gauge is bear work with.

 

[jeffmeh]

If the panel is protected by a 30amp breaker, then you need to run 10awg. If you want to go down to a smaller gauge, you should protect that wiring with the appropriate fuse, upstream.