Quote Originally Posted by slingblade
experience tells me that changing flow switches twice a year may be a little excessive, especially the johnson penn type as i have seen them in the field 10/15 years old and still going strong.
I have seen them last this long too.

I have also seen some that rusted shut in the closed position after 2 years or less.

The take home message is not the time frame, but that they should be periodically checked for proper operation and condition.

It is the ones that fail in a short time that make for happy clients.