Legal Question in Real Estate Law in California

Your willing to engage in a legal battle with your landlord, risk your health, and the health of your son rather than have the cooler repaired?

If you are on a month-to-month rental you have to give 30-days notice. If you are on a lease, you have to wait until the end of the lease. Unfortunately failure to provide heat is a habitability issue that if unrepaired will allow you to break a lease, but failure to provide cooling is not.

Swamp coolers are rrelatively simple devices and should last 25+ years even in Fresno. Unless you want to move for other reasons and have a month-to-month commitment, I'd suggest getting the thing repaired at your own expense (after obtaining an affordable quote, of course).