Vacuum off all the filters, then into the washing machine with the hoses (take the handle off the cylinder one if you can) and some towels, on a hot, long wash (I do 70 degrees for 2 and a half hours). Maybe do this when everyone is out as it does clunk about a bit. Then into the airing cupboard for a few days, try and strech the upright hoses out and keep them streched whilst they dry, it speeds things up.
Should come up like new. If any of the post filters dont, then you needed new ones anyway!