Ok, the first question is did you sign an inventory when you moved in? And again when you moved out? What does the inventory say about the condition of the carpet etc when you moved out compared with when you moved in?
Without an inventory, and a detailed one at that, it's very difficult for the landlord to make any deductions at all.
After 3 years in the property there would have to be a significant amount allowed for fair wear and tear anyway so the landlord wouldnt be allowed to claim the cost of new carpets.
As to the cleaning, people's idea of 'spotless' does vary. Again, you would have to refer to the inventory to see what's been said.
My first reaction would be to ask the landlord to provide copies of the receipts for the �110 that they have spent - they have to provide these. Tell them you are not happy about the deductions and see what they come back with.
Its unusual however for there to be no damage to a property and you should expect to maybe have to pay something, though new carpets are maybe a bit over the top unless you have damaged them.