I purchased this iron from Adafruit
https://www.adafruit.com/product/180
and the tip refuses to heat up. The middle section of the barrel and above towards the handle heats up and cab melt the solder, but the tip from the end to about an inch up doesn't get hot enough to do so. I am unable to work on the talking D20 project because of this. Is it possible to do an exchange to get credit towards a better model iron?