I watched a British recipe that instructed for it to be baked at 180 fan. I live in the states and use a conventional oven. What do I set it at. Also, would the baking time change?
180 fan is 180 degrees Centigrade with the fan on. The general advice when converting from a fan to a non fan oven is increase temperature 15-20 degrees, so the range you are looking for is between 383 and 392 degrees Fahrenheit. If you have a digital stove I'd say set it for 390, if it's a dial you'll need to eyeball it.
180 fan= 200C= 400F I have attached a chart that I use for reference. Note: I did not create this chart.