You could check to see if the pump is still operating. If it fails, the fan will still continue to blow air into the house but since the pad is not receiving any water, it will only blow outside air into the house. It is just a plug in replacement fix and very easy to do. A new pump should cost only about thirty dollars or so. With the cooler running, check to see if the pad is wet . if it is dry, it's a pretty sure bet that the pump is your problem.
Answers & Comments
How do I replace a rigid pad on my Mastercool swamp cooler?
You could check to see if the pump is still operating. If it fails, the fan will still continue to blow air into the house but since the pad is not receiving any water, it will only blow outside air into the house. It is just a plug in replacement fix and very easy to do. A new pump should cost only about thirty dollars or so.
With the cooler running, check to see if the pad is wet . if it is dry, it's a pretty sure bet that the pump is your problem.