Which is why I change my impeller after after I comission in the spring. You confirmed my thoughts that the antifreeze might/ does affect the impeller.
What have you found about the joker valves, although that doesnt sit in the antifreeze solution like an impeller would. Are you looking at the fresh water systems we use and also the pumps. Some people use impeller type pumps for their fresh water and some use diaphram pumps. Most of us flush with PG to winterize.
Dave
A number of thoughts:
* Many joker valves do sit in the solution. It depends on the practice. They stiffen and may be more leak prone. But this is not as critical or difficult an application as a flexible impellor.
* Nitrile is not affected, so the subject does not apply to Raritan or Groco heads... though nitrile is more suseptable to urine, though that is a different topic.
* Yeah, this does point to a problem with fresh water systems. I've had PG ruin strainers and Bill Rossa has good points. But I have also had pipes burst on complex systems that were blown out; a few ounces found there way to a cast fitting at a low point. The notion that pipes can freeze and not burst is about 95% true; fittings burst much more easily and brass valves often don't take much at all (water can get trapped behind the ball).
My current practice is to circulate PG (takes only a few minutes with the valves I added) and then blow out what I can and remove the strainer covers. I do NOT believe in taking pipes apart; I've spent too much time chasing leaks. I'm sure this last depends a great deal on the type of piping.