I have a front load washer and dryer stacked. I don't think there's any restrictions on front loaders being stacked on top of each other. I used to have a top load washer with a front load dryer stack - the top load washer lid was a pain in the a**. I like the front load much better!
I would check through your Bosch manual or get a new one online. Just check online for the Bosch brand front loader washer - 300 series for a new manual. Or, contact the store that you purchased it and find out where you can receive help.
