Shelf life of anti-freeze?

[autoxer]

Anyone know if anti-freeze goes "bad", opened and/or factory sealed?

 

[Bama Rambler]

What type Anti-freeze?

Engine antifreeze concentrate doesn't, premixed does and it's anywhere from 1 to 5 years.

RV antifreeze, if kept in the original container has a shelf life of at least one year and I've read up to ten years.

 

[autoxer]

Pool / RV antifreeze. Are they (pool/RV AF that is) all Propylene Glycol BTW? If not, any preferences?

Also, any reason to use / not use concentrated anti-freeze (typically finding it in qts) instead of the standard diluted stuff typically found in gals? The logic in me says pour the concentrate in the line after blowing them and, *if* your plug doesn't quite hold or whatever let the water that gets in do the diluting.

[edit: spelling ability falls off 2 hrs past bedtime]

 

[Bama Rambler]

All I've seen are Propylene Glycol. I like your idea about adding it full strength. It may waste some but if it gives you peace of mind then it's worth it.

 

[jhill28590]

Anyone know if anti-freeze goes "bad", opened and/or factory sealed?

Officially, most Propylene Glycol products have a shelf life of two years. Oxygen will decompose Propylene Glycol, so will heat above 100 degrees F or direct sunlight. So keep it in a cool shady spot.

Yes, Propylene Glycol (RV Antifreeze) is used as a food additive and in eye drops, but I don't like to put a lot of it in my pool. So I get a large container of vinegar from Costco and use up the vinegar for cooking. I keep the over-sized jug for the pool. I clean it with fresh water and fill it with Propylene Glycol. Then after I clean and plug out the skimmer for winterization, I place a jug filled with Propylene Glycol in each skimmer. By spring the water has returned to normal levels and the jug of Propylene Glycol keeps the ice from breaking the skimmer.

I do put some Propylene Glycol in the return lines near the pump. This uses up some each year and this keeps the Propylene Glycol fresh enough for me.