I know it's hard to find a new job in this economy and based on your paycheck to paycheck comments - you can't just quit and look for a new job. Keep in mind that if you suffer from heat exhaustion and require medical attention this will likely be a workers' compensation claim. If this occurs, contact a local workers' compensation attorney as soon as you can.
Look for a new job, where there is A/C and running water. The bar is not very high; Starbucks and McDonalds usually meet that criteria.
I represent Employers, but I can recommend Worker Attorneys in So Cal if you ask.