The Series 1 is designed so that on the off chance that you encounter reliability issues with your machine, all the critical components in the tool head can be accessed in just a few minutes. The Hot End is accessible by undoing a single bolt.
Before doing anything, COOL DOWN the Hot End and UNPLUG your Series 1 from the wall as well as your computer. Make sure there is no filament inserted in the hot end.
It's not a must, but I recommend you take off the fan bracket, as shown above. It just makes everything easier. Below you can see the result of that operation:
Awesome! Now we need only to undo the single bolt holding the hot end in place! We also must undo the two Molex connectors that are connected to the hot end; the temperature sensor and the heater wire:
When you finish undoing that bolt, the front end of the clamp will come right off. And once you're done there, your setup should look like this:
Yay! You've reached the hot end. Making sure it is totally cooled down, simply pull the offending hot end out, and put the new one in.
Now, putting the new hot end in is nine-tenths as easy as taking it out. Just make sure that the new hot end is all the way in there, and that the hole in the hot end lines up with the hole formed by both sides of the clamp. You can do this by matching the slit of the back clamp (the part of the lower section of the tool head that you didn't remove) to the hole in the top of the hot end.
Then put everything back together: the bolt, the temp sensor and heater wire connectors, and the fan bracket.
And, you're done. If you need any more help, feel free to look around at support.typeamachines.com or forum.typeamachines.com for access to our vibrant customer community.
If you still need help, you can start a support ticket from support.typeamachines.com.