I have a 1 yr old high efficiency gas furnace. The water it produces is pumped to the outside of the house. Last winter I noticed the water in the tube was freezing, causing the water to backup and flood under the furnace. I shortened the length of the tube in the spring hoping that if the water didn't travel as far it might not freeze. However yesterday I noticed it happened again. I have temporarily connected a tube to pump water directly into the floor drain instead.

I would like to know if I can better insulate the tube outside to prevent freezing. There is currently a black rubber tube surrounding the clear plastic tube.

I've thought about pumping water to the laundry room sink instead of outside, but am wondering if there's a simpler or better solution before doing that. Any advice would be greatly appreciated.

thank you.