What's the best size wire for electric furnace? Running it from the outside pole to the furnace, about 60 ft.aluminum wire now,but trips breaker.

Hello, thank you for your question. This answer will require a more technical response. Please reach out to our technical team at cabletechsupport@southiwre.com for a detailed explanation of your question.

Your question cannot be answered without more information on the electric furnace. Electric furnaces typically are sized by KW. 15 KW, 20 KW and 25 KW are the most common sizes, but 5 KW, 7.5 KW and 10 KW sizes are also available. In addition, you are only allowed one circuit to a dwelling. That means there must be a panel at the house and the furnace circuit must originate from that panel and not from the pole. One other thing, most electric furnaces are labelled at the main lugs that the lugs are suitable for copper wiring only. There may be exceptions to this on your furnace, please provide the manufacturer and model number.