Can I connect an American 220 Volt dryer / Air conditioer to a transformer?
Only if it is a single phase appliance, If it is a two phase, you cannot connect and American 220 Volt dryer to a transformer. Voltage transformers are made to convert single phase 110 or 220 volt. American 220 volt consists of 2 phase of 110 volt and European 220 volt consists of 1 phase of 220 volt.