Cheap clumping cat litter has been a bad idea, now whole house smells like ammonia, HELP?

I have 4 indoor cats and I clean the box regularly. I had recently purchased some cheap cat litter from the local grocery store due to finances. I filled my cat boxes, and left for vacation. My pet sitter cleaned the boxes daily, and when I came home the cat urine smell was SO strong I've had to open up my house every single day, it's almost been toxic. I couldn't figure out what was going on, until I cleaned the litter box myself, to find that the cheap cat litter makes the clumps fall apart in an instant, leaving the pee smell stronger than I have ever smelled in my life, and it's whats making my whole house reek. It's so bad when I run the a/c it picks up the smell through the a/c which ultimatly makes my entire house smell.

Now its to the point where I can't run the a/c. This is a disaster and its just destroying everything.

I've just cleaned out all my litter boxes and replaced it with fresh arm n hammer cat litter (which works wonders) . My house though is screwed..i'm thinking.

I've changed my a/c filter, washed blankets etc, but the smell is still there and coming through.

Please help, I don't know what to do, other than put the litter boxes out on the lanai and get them out of the house. I really don't want to do this because I live in SW FL and the humidity and what not will just carry any odor. It's a bad time of year to do this. I've got to get this smell out of my house!!!!!!

HELP!!!!!!!!!!!!!