No, the landlord does NOT have the right to do this. If you are late with the rent, the landlord may be able to evict you, but he or she has to do so properly, by bringing an action through the courts. A landlord may NOT resort to "self-help" by changing locks, turning off utilities, or depriving tenants of air conditioning (or heat). Doing so could make the landlord liable for illegal eviction (e.g. for trying to force you out), for a violation of the implied warranty of habitability (for making the premises unfit for residence), and possibly for breach of the lease (if it's clear you were renting a place with air conditioning). If the landlord  will not relent, you should speak with an attorney, and if you can't afford one, try contacting Legal Services. Good luck.