Is it safe to run a refrigerator supply line behind the electric range? My kitchen is U shaped. My plumber wants $100 to install one but they only cost $10 at Home Depot. I understand his will be better quality but will the stuff at Home Depot be safe when ran behind the stove?
Yes it will be fine.
Do not use a saddle valve to connect the line to your supply line.
Instead change the shut off valve you have there now to a 2, way valve.
Saddle valves tend to leak, plug up, and do not even meet code in some places.